Define two bfd_targets for absence and presence of leading

	Define two bfd_targets for absence and presence of leading
	underscore on symbols.  Make sure to only link same kind.
	* elf32-cris.c (cris_elf_object_p,
	cris_elf_final_write_processing, cris_elf_print_private_bfd_data,
	cris_elf_merge_private_bfd_data): New.
	(elf_backend_object_p, elf_backend_final_write_processing,
	bfd_elf32_bfd_print_private_bfd_data,
	bfd_elf32_bfd_merge_private_bfd_data): Define.
	<Target vector definition>: Include elf32-target.h twice with
	different macro settings:
	(TARGET_LITTLE_SYM): First as bfd_elf32_cris_vec, then as
	bfd_elf32_us_cris_vec.
	(TARGET_LITTLE_NAME): First as "elf32-cris", then "elf32-us-cris".
	(elf_symbol_leading_char): First as 0, then '_'.
	(INCLUDED_TARGET_FILE): Define for second include of elf32-target.h.
	* config.bfd (cris-*-*): Add bfd_elf32_us_cris_vec to targ_selvecs.
	* configure.in (bfd_elf32_cris_vec, cris_aout_vec): New vector.
	* configure: Regenerate.
	* targets.c: Declare bfd_elf32_us_cris_vec.
	* po/bfd.pot: Regenerate.