Move microblaze relax info to target specific data

Move microblaze relax info to target specific data

Target specific data shouldn't be put in struct bfd_section.

	* section.c (struct bfd_section): Delete relax and relax_count.
	(BFD_FAKE_SECTION): Adjust to suit.
	(struct relax_table): Move to..
	* elf32-microblaze.c (struct relax_table): ..here.
	(struct _microblaze_elf_section_data): New.
	(microblaze_elf_section_data): Define.
	(microblaze_elf_new_section_hook): New function.
	(bfd_elf32_new_section_hook): Define.
	(calc_fixup): Return a size_t.  Adjust to suit new location of
	relax and relax_count.
	(microblaze_elf_relax_section): Adjust to suit new location of
	relax and relax_count.  Make some variables size_t.
	* bfd-in2.h: Regenerate.