Add LDPT_REGISTER_CLAIM_FILE_HOOK_V2 linker plugin hook [GCC PR109128]

Add LDPT_REGISTER_CLAIM_FILE_HOOK_V2 linker plugin hook [GCC PR109128]

This is one part of the fix for GCC PR109128, along with a
corresponding GCC change.  Without this patch, what happens in the
linker, when an unused object in a .a file has offload data, is that
elf_link_is_defined_archive_symbol calls bfd_link_plugin_object_p,
which ends up calling the plugin's claim_file_handler, which then
records the object as one with offload data. That is, the linker never
decides to use the object in the first place, but use of this _p
interface (called as part of trying to decide whether to use the
object) results in the plugin deciding to use its offload data (and a
consequent mismatch in the offload data present at runtime).

The new hook allows the linker plugin to distinguish calls to
claim_file_handler that know the object is being used by the linker
(from ldmain.c:add_archive_element), from calls that don't know it's
being used by the linker (from elf_link_is_defined_archive_symbol); in
the latter case, the plugin should avoid recording the object as one
with offload data.

	bfd/
	* plugin.c (struct plugin_list_entry): Add claim_file_v2.
	(register_claim_file_v2): New.
	(try_load_plugin): Use LDPT_REGISTER_CLAIM_FILE_HOOK_V2.
	(ld_plugin_object_p): Take second argument.
	(bfd_link_plugin_object_p): Update call to ld_plugin_object_p.
	(register_ld_plugin_object_p): Update argument prototype.
	(bfd_plugin_object_p): Update call to ld_plugin_object_p.
	* plugin.h (register_ld_plugin_object_p): Update argument
	prototype.

	include/
	* plugin.api.h (ld_plugin_claim_file_handler_v2)
	(ld_plugin_register_claim_file_v2)
	(LDPT_REGISTER_CLAIM_FILE_HOOK_V2): New.
	(struct ld_plugin_tv): Add tv_register_claim_file_v2.

	ld/
	* plugin.c (struct plugin): Add claim_file_handler_v2.
	(LDPT_REGISTER_CLAIM_FILE_HOOK_V2): New.
	(plugin_object_p): Add second argument.  Update call to
	plugin_call_claim_file.
	(register_claim_file_v2): New.
	(set_tv_header): Handle LDPT_REGISTER_CLAIM_FILE_HOOK_V2.
	(plugin_call_claim_file): Add argument known_used.
	(plugin_maybe_claim): Update call to plugin_object_p.
	* testplug.c, testplug2.c, testplug3.c, testplug4.c: Handle
	LDPT_REGISTER_CLAIM_FILE_HOOK_V2.
	* testsuite/ld-plugin/plugin-1.d, testsuite/ld-plugin/plugin-10.d,
	testsuite/ld-plugin/plugin-11.d, testsuite/ld-plugin/plugin-13.d,
	testsuite/ld-plugin/plugin-14.d, testsuite/ld-plugin/plugin-15.d,
	testsuite/ld-plugin/plugin-16.d, testsuite/ld-plugin/plugin-17.d,
	testsuite/ld-plugin/plugin-18.d, testsuite/ld-plugin/plugin-19.d,
	testsuite/ld-plugin/plugin-2.d, testsuite/ld-plugin/plugin-26.d,
	testsuite/ld-plugin/plugin-3.d, testsuite/ld-plugin/plugin-30.d,
	testsuite/ld-plugin/plugin-4.d, testsuite/ld-plugin/plugin-5.d,
	testsuite/ld-plugin/plugin-6.d, testsuite/ld-plugin/plugin-7.d,
	testsuite/ld-plugin/plugin-8.d, testsuite/ld-plugin/plugin-9.d:
	Update test expectations.