* elf.c (setup_group): Set SEC_LINK_ONCE on GRP_COMDAT groups.

	* elf.c (setup_group): Set SEC_LINK_ONCE on GRP_COMDAT groups.
	(bfd_section_from_shdr): Likewise.  Set section name of group
	sections from signature.
	(group_signature): Split out from setup_group.  Ensure symbol table
	is available.
	(bfd_elf_discard_group): New function.
	(_bfd_elf_make_section_from_shdr): Don't set SEC_LINK_ONCE on
	.gnu.linkonce* sections if they are members of a group.
	(set_group_contents): Set GRP_COMDAT flag.
	* section.c (bfd_discard_group): New function.
	* bfd-in.h (bfd_elf_discard_group): Declare.
	* bfd-in2.h: Regenerate.
	* elf-bfd.h (struct bfd_elf_section_data): Add linkonce_p field.
	(elf_linkonce_p): Define.