* config.bfd (sh-*-linux*): Use bfd_elf*_sh64*lin_vec as sh64

	* config.bfd (sh-*-linux*): Use bfd_elf*_sh64*lin_vec as sh64
	vectors in target_selvecs.
	(shle-*-netbsdelf*): Use bfd_elf*_sh64*nbsd_vec as sh64 vectors
	in target_selvecs.
	(sh-*-netbsdelf*): Likewise.
	* configure.in (assocvecs): New variable.  Handle assocvecs like
	selvecs.
	* configure: Regenerate.
	* format.c (bfd_check_format_matches): Store bfd_target pointers
	in matching_vector instead of target names.  Select first target
	from bfd_associated_vector that matches a list of ambiguous targets.
	* targets.c (_bfd_associated_vector): New array.
	(bfd_associated_vector): New variable.
	(_bfd_target_vector): Add bfd_elf*_sh64*lin_vec.
	* libbfd-in.h (bfd_associated_vector): Declare.
	* libbfd.h: Regenerate.