* archures (bfd_mach_arc_base): #define.

	* archures (bfd_mach_arc_base): #define.
	(bfd_mach_arc_host, bfd_mach_arc_graphics, bfd_mach_arc_audio): Ditto.
	* cpu-arc.c (arch_info_struct): Define entries for each cpu variant.
	(bfd_arc_arch): Link each one in.
	(arc_get_mach): New function.
	* elf32-arc.c (arc_info_to_howto_rel): Renamed from arc_info_to_howto.
	(elf_info_to_howto_rel): Update.
	(arc_elf_object_p, arc_elf_final_write_processing): New functions.
	(elf_backend_object_p): Define.
	(elf_backend_final_write_processing): Define.
	(USE_REL): Define.