Changes to support linker relaxing of embedded MIPS PIC code to

	Changes to support linker relaxing of embedded MIPS PIC code to
	use a five instruction sequence for funtion calls which are out of
	range of the bal instruction.
	* libecoff.h (struct ecoff_section_tdata): Define.
	(ecoff_section_data): Define.
	(ecoff_bfd_relax_section): Don't define.
	* ecoff.c (ecoff_final_link_debug_accumulate): Don't read or free
	the debugging information if it has already been read.
	(ecoff_indirect_link_order): Handle _cooked_size being different
	from _raw_size.  Don't reread the contents or the relocs if they
	have already been read in.
	* coff-mips.c (mips_howto_table): Change bitsize of PCREL16 from
	18 to 16.
	(PCREL16_EXPANSION_ADJUSTMENT): Define.
	(mips_relocate_refhi): Take adjust argument.
	(mips_relocate_section): Handle reloc offsets stored in section
	used_by_bfd field.  Call mips_relax_pcrel16 to handle details of
	expanding an out of range PCREL16.  Keep trace of adjustments
	required by expansions.  Set s and unset h when converting a reloc
	from undefined to section.  Change handling of PC relative relocs:
	if against a section, they are correct in the object file, if
	against an external symbol they are pcrel_offset.
	(mips_relax_section): New function.
	(mips_relax_pcrel16): New function.
	(ecoff_bfd_relax_section): Define.
	* coff-alpha.c (ecoff_bfd_relax_section): Define.
	* ecofflink.c (bfd_ecoff_debug_accumulate): Handle adjustments
	built by mips_relax_section when writing out addresses.
	* elf32-mips.c (mips_elf_read_ecoff_info): Clear adjust field.