x86; Don't add elf64-x86-64.lo nor elf64.lo together with elfxx-x86.lo

x86; Don't add elf64-x86-64.lo nor elf64.lo together with elfxx-x86.lo

Don't set r_info and r_sym fields in _bfd_x86_elf_link_hash_table_create.
Instead, set them in _bfd_x86_elf_link_setup_gnu_properties.  We can
avoid adding elf64-x86-64.lo and elf64.lo together with elfxx-x86.lo to
bfd_backends.

	* configure.ac (bfd_backends): Don't add elf64-x86-64.lo nor
	elf64.lo together with elfxx-x86.lo for 64-bit BFD.
	* configure: Regenerated.
	* elf32-i386.c (elf_i386_link_setup_gnu_properties): Set r_info
	and r_sym fields of plt_layout.
	* elf64-x86-64.c (elf_x86_64_link_setup_gnu_properties):
	Likewise.
	* elfxx-x86.c (elf_x86_64_is_reloc_section): Remove BFD64 check.
	(_bfd_x86_elf_link_hash_table_create): Likewise.  Don't set
	r_info nor r_sym fields.
	(_bfd_x86_elf_link_setup_gnu_properties): Set r_info and r_sym
	fields of htab.
	* elfxx-x86.h (elf_x86_plt_layout_table): Add r_info and r_sym.