PR ld/12762

	PR ld/12762
bfd/
	* elflink.c (_bfd_elf_section_already_linked): Return matched
	status.  Remove COFF comdat section handling.
	* linker.c (_bfd_generic_section_already_linked): Return matched
	status.  Don't set SEC_GROUP in l_flags for plugin entries.
	(bfd_section_already_linked): Update prototype.
	* targets.c (_section_already_linked): Likewise.
	* elf-bfd.h (_bfd_elf_section_already_linked): Likewise.
	* libbfd-in.h (_bfd_generic_section_already_linked): Likewise.
	(_bfd_nolink_section_already_linked): Update.
	* libbfd.h: Regenerate.
	* bfd-in2.h: Regenerate.
ld/
	* plugin.c (add_symbols): Exclude comdat_key symbols from symbol
	table if already seen.