Add XCOFF64 support.

	Add XCOFF64 support.

	bfd:
	* Makefile.am (coff64-rs6000.lo): New rule.
	* Makefile.in: Regenerate.
	* coff-rs6000.c (xcoff_mkobject, xcoff_copy_private_bfd_data,
	xcoff_is_local_label_name, xcoff_rtype2howto,
	xcoff_reloc_type_lookup, xcoff_slurp_armap, xcoff_archive_p,
	xcoff_read_ar_hdr, xcoff_openr_next_archived_file, xcoff_write_armap,
	xcoff_write_archive_contents): No longer static, and prefix with _bfd_.
	(NO_COFF_SYMBOLS): Define.
	(xcoff64_swap_sym_in, xcoff64_swap_sym_out, xcoff64_swap_aux_in,
	xcoff64_swap_aux_out): New functions; handle xcoff symbol tables
	internally.
	(MINUS_ONE): New macro.
	(xcoff_howto_tabl, xcoff_reloc_type_lookup): Add 64 bit POS
	relocation.
	(coff_SWAP_sym_in, coff_SWAP_sym_out, coff_SWAP_aux_in,
	coff_SWAP_aux_out): Map to the new functions.
	* coff64-rs6000.c: New file.
	* libcoff.h (bfd_coff_backend_data): Add new fields
	_bfd_coff_force_symnames_in_strings and
	_bfd_coff_debug_string_prefix_length.
	(bfd_coff_force_symnames_in_strings,
	bfd_coff_debug_string_prefix_length): New macros for above fields.
	* coffcode.h (coff_set_arch_mach_hook): Handle XCOFF64 magic.
	Set machine to 620 for XCOFF64.  Use bfd_coff_swap_sym_in instead
	of using coff_swap_sym_in directly.
	(FORCE_SYMNAMES_IN_STRINGS): New macro, defined for XCOFF64.
	(coff_set_flags) Set magic for XCOFF64.
	(coff_compute_section_file_positions): Add symbol name length to
	string section length if bfd_coff_debug_string_prefix_length is
	true.
	(coff_write_object_contents): Don't do reloc overflow for XCOFF64.
	(coff_slurp_line_table): Use bfd_coff_swap_lineno_in instead of
	using coff_swap_lineno_in directly.
	(bfd_coff_backend_data): Add _bfd_coff_force_symnames_in_strings
	and _bfd_coff_debug_string_prefix_length fields.
	* coffgen.c (coff_fix_symbol_name, coff_write_symbols): Force
	symbol names into strings table when
	bfd_coff_force_symnames_in_strings is true.
	* coffswap.h (MAX_SCNHDR_NRELOC, MAX_SCNHDR_NLNNO, GET_RELOC_VADDR,
	SET_RELOC_VADDR): New macros.
	(coff_swap_reloc_in, coff_swap_reloc_out): Use above macros.
	(coff_swap_aux_in, coff_swap_aux_out): Remove RS6000COFF_C
	code.
	(coff_swap_aouthdr_in, coff_swap_aouthdr_out): Handle XCOFF64
	changes within RS6000COFF_C specific code.
	(coff_swap_scnhdr_out): Use PUT_SCNHDR_NLNNO, PUT_SCNHDR_NRELOC,
	MAX_SCNHDR_NRELOC, and MAX_SCNHDR_NLNNO.
	* reloc.c (bfd_perform_relocation, bfd_install_relocation):
	Extend existing hack on target name.
	* xcofflink.c (XCOFF_XVECP): Extend existing hack on
	target name.
	* coff-tic54x.c (ticof): Keep up to date with new fields
	in bfd_coff_backend_data.
	* config.bfd: Add bfd_powerpc_64_arch to targ_arch and define
	targ_selvecs to include rs6000coff64_vec for rs6000.
	* configure.in: Add rs6000coff64_vec case.
 	* cpu-powerpc.c: New bfd_arch_info_type.

	gas:
	* as.c (parse_args): Allow md_parse_option to override -a listing
	option.
	* config/obj-coff.c (add_lineno): Change type of offset parameter
	from "int" to "bfd_vma."
	* config/tc-ppc.c (md_pseudo_table): Add "llong" and "machine."
	(ppc_mach, ppc_subseg_align, ppc_target_format): New.
	(ppc_change_csect): Align correctly for XCOFF64.
	(ppc_machine): New function, which discards "ppc_machine" line.
	(ppc_tc): Cons for 8 when code is 64 bit.
	(md_apply_fix3): Don't check operand->insert.  Handle 64 bit
	relocations.
	(md_parse_option): Handle -a64 and -a32.
	(ppc_xcoff64): New.
	* config/tc-ppc.h (TARGET_MACH): Define.
	(TARGET_FORMAT): Move to function.
	(SUB_SEGMENT_ALIGN): Use ppc_subseg_align.

	include:
	* include/coff/rs6k64.h: New file.

	opcodes:
	* configure.in: Add bfd_powerpc_64_arch.
	* disassemble.c (disassembler): Use print_insn_big_powerpc for
	64 bit code.