libstdc++: Ensure c++NN effective target present in all C++17 tests

libstdc++: Ensure c++NN effective target present in all C++17 tests

Also reorder some directives so that the dg-options setting -std=gnu++17
comes before the dg-do that requires c++17.

libstdc++-v3/ChangeLog:

	* testsuite/17_intro/headers/c++2017/all_attributes.cc: Add
	c++17 effective-target.
	* testsuite/17_intro/headers/c++2017/all_no_exceptions.cc:
	Likewise.
	* testsuite/17_intro/headers/c++2017/all_no_rtti.cc: Likewise.
	* testsuite/17_intro/headers/c++2017/all_pedantic_errors.cc:
	Likewise.
	* testsuite/17_intro/headers/c++2017/operator_names.cc:
	Likewise.
	* testsuite/17_intro/headers/c++2017/stdc++.cc: Likewise.
	* testsuite/17_intro/headers/c++2017/stdc++_multiple_inclusion.cc:
	Likewise.
	* testsuite/18_support/uncaught_exceptions/uncaught_exceptions.cc:
	Likewise.
	* testsuite/19_diagnostics/error_code/is_error_code_v.cc:
	Likewise.
	* testsuite/20_util/any/assign/1.cc: Likewise.
	* testsuite/20_util/any/assign/2.cc: Likewise.
	* testsuite/20_util/any/assign/emplace.cc: Likewise.
	* testsuite/20_util/any/assign/exception.cc: Likewise.
	* testsuite/20_util/any/assign/self.cc: Likewise.
	* testsuite/20_util/any/cons/1.cc: Likewise.
	* testsuite/20_util/any/cons/2.cc: Likewise.
	* testsuite/20_util/any/cons/aligned.cc: Likewise.
	* testsuite/20_util/any/cons/explicit.cc: Likewise.
	* testsuite/20_util/any/cons/in_place.cc: Likewise.
	* testsuite/20_util/any/cons/nontrivial.cc: Likewise.
	* testsuite/20_util/any/make_any.cc: Likewise.
	* testsuite/20_util/any/misc/any_cast.cc: Likewise.
	* testsuite/20_util/any/misc/any_cast_no_rtti.cc: Likewise.
	* testsuite/20_util/any/misc/swap.cc: Likewise.
	* testsuite/20_util/any/modifiers/1.cc: Likewise.
	* testsuite/20_util/any/observers/type.cc: Likewise.
	* testsuite/20_util/any/requirements.cc: Likewise.
	* testsuite/20_util/any/typedefs.cc: Likewise.
	* testsuite/20_util/as_const/1.cc: Likewise.
	* testsuite/20_util/as_const/rvalue_neg.cc: Likewise.
	* testsuite/20_util/bind/is_placeholder_v.cc: Likewise.
	* testsuite/20_util/bool_constant/requirements.cc: Likewise.
	* testsuite/20_util/duration/requirements/treat_as_floating_point_v.cc:
	Likewise.
	* testsuite/20_util/duration_cast/rounding.cc: Likewise.
	* testsuite/20_util/enable_shared_from_this/members/weak_from_this.cc:
	Likewise.
	* testsuite/20_util/function_objects/invoke/59768.cc: Likewise.
	* testsuite/20_util/function_objects/not_fn/1.cc: Likewise.
	* testsuite/20_util/function_objects/searchers.cc: Likewise.
	* testsuite/20_util/in_place/requirements.cc: Likewise.
	* testsuite/20_util/is_invocable/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_invocable/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/is_invocable/value.cc: Likewise.
	* testsuite/20_util/is_nothrow_invocable/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_nothrow_invocable/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/is_nothrow_swappable/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_nothrow_swappable/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/is_nothrow_swappable/value.cc: Likewise.
	* testsuite/20_util/is_nothrow_swappable_with/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_nothrow_swappable_with/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/is_nothrow_swappable_with/value.cc:
	Likewise.
	* testsuite/20_util/is_swappable/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_swappable/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/is_swappable/value.cc: Likewise.
	* testsuite/20_util/is_swappable_with/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_swappable_with/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/is_swappable_with/value.cc: Likewise.
	* testsuite/20_util/logical_traits/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/logical_traits/requirements/typedefs.cc:
	Likewise.
	* testsuite/20_util/logical_traits/value.cc: Likewise.
	* testsuite/20_util/optional/constexpr/make_optional.cc: Likewise.
	* testsuite/20_util/optional/constexpr/observers/2.cc: Likewise.
	* testsuite/20_util/optional/constexpr/observers/3.cc: Likewise.
	* testsuite/20_util/optional/hash.cc: Likewise.
	* testsuite/20_util/pair/swap_cxx17.cc: Likewise.
	* testsuite/20_util/ratio/requirements/ratio_equal_v.cc: Likewise.
	* testsuite/20_util/shared_ptr/requirements/weak_type.cc:
	Likewise.
	* testsuite/20_util/specialized_algorithms/memory_management_tools/1.cc:
	Likewise.
	* testsuite/20_util/tuple/apply/1.cc: Likewise.
	* testsuite/20_util/tuple/make_from_tuple/1.cc: Likewise.
	* testsuite/20_util/tuple/swap_cxx17.cc: Likewise.
	* testsuite/20_util/tuple/tuple_size_v.cc: Likewise.
	* testsuite/20_util/unique_ptr/specialized_algorithms/swap_cxx17.cc:
	Likewise.
	* testsuite/20_util/uses_allocator/requirements/uses_allocator_v.cc:
	Likewise.
	* testsuite/20_util/variant/any.cc: Likewise.
	* testsuite/20_util/variant/compile.cc: Likewise.
	* testsuite/20_util/variant/hash.cc: Likewise.
	* testsuite/20_util/variant/index_type.cc: Likewise.
	* testsuite/20_util/variant/run.cc: Likewise.
	* testsuite/20_util/void_t/1.cc: Likewise.
	* testsuite/21_strings/basic_string/79162.cc: Likewise.
	* testsuite/21_strings/basic_string/cons/char/7.cc: Likewise.
	* testsuite/21_strings/basic_string/cons/wchar_t/7.cc: Likewise.
	* testsuite/21_strings/basic_string/lwg2758.cc: Likewise.
	* testsuite/21_strings/basic_string/lwg2946.cc: Likewise.
	* testsuite/21_strings/basic_string/modifiers/append/char/4.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/append/wchar_t/4.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/assign/char/4.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/assign/wchar_t/4.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/insert/char/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/insert/wchar_t/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/replace/char/7.cc:
	Likewise.
	* testsuite/21_strings/basic_string/modifiers/replace/wchar_t/7.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/compare/char/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/compare/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/data/char/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/data/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/find/char/5.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operations/find/wchar_t/5.cc:
	Likewise.
	* testsuite/21_strings/basic_string/operators/char/5.cc: Likewise.
	* testsuite/21_strings/basic_string/operators/wchar_t/5.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/capacity/1.cc: Likewise.
	* testsuite/21_strings/basic_string_view/cons/char/1.cc: Likewise.
	* testsuite/21_strings/basic_string_view/cons/char/2.cc: Likewise.
	* testsuite/21_strings/basic_string_view/cons/char/3.cc: Likewise.
	* testsuite/21_strings/basic_string_view/cons/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/cons/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/cons/wchar_t/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/char/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/char/empty.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/char/front_back.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/wchar_t/empty.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/element_access/wchar_t/front_back.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/include.cc: Likewise.
	* testsuite/21_strings/basic_string_view/inserters/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/inserters/char/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/inserters/char/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/inserters/pod/10081-out.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/inserters/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/inserters/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/inserters/wchar_t/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/literals/types-char8_t.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/literals/types.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/literals/values-char8_t.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/literals/values.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/modifiers/remove_prefix/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/modifiers/remove_prefix/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/modifiers/remove_suffix/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/modifiers/remove_suffix/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/compare/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/compare/char/13650.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/compare/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/compare/wchar_t/13650.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/copy/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/copy/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/data/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/data/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/char/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/char/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/char/4.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/wchar_t/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/find/wchar_t/4.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/rfind/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/rfind/char/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/rfind/char/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/rfind/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/rfind/wchar_t/2.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/rfind/wchar_t/3.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/string_conversion/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/substr/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/operations/substr/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/range_access/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/range_access/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char16_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char32_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/char8_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/explicit_instantiation/wchar_t/1.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/requirements/typedefs.cc:
	Likewise.
	* testsuite/21_strings/basic_string_view/typedefs.cc: Likewise.
	* testsuite/21_strings/basic_string_view/types/1.cc: Likewise.
	* testsuite/23_containers/array/specialized_algorithms/swap_cxx17.cc:
	Likewise.
	* testsuite/23_containers/map/modifiers/extract.cc: Likewise.
	* testsuite/23_containers/map/modifiers/insert_or_assign/1.cc:
	Likewise.
	* testsuite/23_containers/map/modifiers/merge.cc: Likewise.
	* testsuite/23_containers/map/modifiers/try_emplace/1.cc: Likewise.
	* testsuite/23_containers/multimap/modifiers/extract.cc: Likewise.
	* testsuite/23_containers/multimap/modifiers/merge.cc: Likewise.
	* testsuite/23_containers/multiset/modifiers/extract.cc: Likewise.
	* testsuite/23_containers/multiset/modifiers/merge.cc: Likewise.
	* testsuite/23_containers/set/modifiers/extract.cc: Likewise.
	* testsuite/23_containers/set/modifiers/merge.cc: Likewise.
	* testsuite/23_containers/unordered_map/modifiers/extract.cc:
	Likewise.
	* testsuite/23_containers/unordered_map/modifiers/insert_or_assign.cc:
	Likewise.
	* testsuite/23_containers/unordered_map/modifiers/merge.cc:
	Likewise.
	* testsuite/23_containers/unordered_map/modifiers/try_emplace.cc:
	Likewise.
	* testsuite/23_containers/unordered_multimap/modifiers/extract.cc:
	Likewise.
	* testsuite/23_containers/unordered_multimap/modifiers/merge.cc:
	Likewise.
	* testsuite/23_containers/unordered_multiset/modifiers/extract.cc:
	Likewise.
	* testsuite/23_containers/unordered_multiset/modifiers/merge.cc:
	Likewise.
	* testsuite/23_containers/unordered_set/modifiers/extract.cc:
	Likewise.
	* testsuite/23_containers/unordered_set/modifiers/merge.cc:
	Likewise.
	* testsuite/24_iterators/headers/iterator/range_access_c++17.cc:
	Likewise.
	* testsuite/24_iterators/headers/iterator/synopsis_c++17.cc:
	Likewise.
	* testsuite/25_algorithms/clamp/1.cc: Likewise.
	* testsuite/25_algorithms/clamp/2.cc: Likewise.
	* testsuite/25_algorithms/clamp/constexpr.cc: Likewise.
	* testsuite/25_algorithms/clamp/requirements/explicit_instantiation/1.cc:
	Likewise.
	* testsuite/25_algorithms/clamp/requirements/explicit_instantiation/pod.cc:
	Likewise.
	* testsuite/26_numerics/headers/cmath/functions_std_c++17.cc:
	Likewise.
	* testsuite/26_numerics/headers/cmath/special_functions_global.cc:
	Likewise.
	* testsuite/27_io/basic_ostream/inserters_other/char/lwg2221.cc:
	Likewise.
	* testsuite/29_atomics/atomic/is_always_lock_free.cc: Likewise.
	* testsuite/29_atomics/atomic_integral/is_always_lock_free.cc:
	Likewise.
	* testsuite/30_threads/shared_lock/70766.cc: Likewise.
	* testsuite/30_threads/shared_mutex/cons/1.cc: Likewise.
	* testsuite/30_threads/shared_mutex/cons/assign_neg.cc:
	Likewise.
	* testsuite/30_threads/shared_mutex/cons/copy_neg.cc:
	Likewise.
	* testsuite/30_threads/shared_mutex/requirements/standard_layout.cc:
	Likewise.
	* testsuite/30_threads/shared_mutex/try_lock/1.cc: Likewise.
	* testsuite/30_threads/shared_mutex/try_lock/2.cc: Likewise.
	* testsuite/30_threads/shared_mutex/unlock/1.cc: Likewise.