cstring (memchr, [...]): Provide inlines only if __CORRECT_ISO_CPP_STRING_H_PROTO...

cstring (memchr, [...]): Provide inlines only if __CORRECT_ISO_CPP_STRING_H_PROTO is not defined.

	* include/c_std/cstring (memchr, strchr, strpbrk, strrchr, strstr):
	Provide inlines only if __CORRECT_ISO_CPP_STRING_H_PROTO is not
	defined.
	* include/c_std/cwchar (wcschr, wcspbrk, wcsrchr, wcsstr, wmemchr):
	Provide inlines only if __CORRECT_ISO_CPP_WCHAR_H_PROTO is not
	defined.
	* include/c_global/cstring (memchr, strchr, strpbrk, strrchr, strstr):
	Provide inlines only if __CORRECT_ISO_CPP_STRING_H_PROTO is not
	defined.
	* include/c_global/cwchar (wcschr, wcspbrk, wcsrchr, wcsstr, wmemchr):
	Provide inlines only if __CORRECT_ISO_CPP_WCHAR_H_PROTO is not
	defined.
	* testsuite/21_strings/c_strings/char_t/2.cc (test02): If first
	argument is const char *, assign result to const char * var, not
	char *.
	* testsuite/21_strings/c_strings/wchar_t/2.cc (test02): If first
	argument is const wchar_t *, assign result to const wchar_t * var, not
	wchar_t *.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>
From-SVN: r143773