* external.h: Fix typo.

	* external.h: Fix typo.
	* mips.h: Add/Extend many comments with reference to the MIPS ELF64
	spec v. 2.4, available at e.g.
	ftp://oss.sgi.com/pub/linux/mips/doc/ABI/ELF64.ps.
	(EF_MIPS_UCODE): Define.
	(EF_MIPS_OPTIONS_FIRST): Define.
	(EF_MIPS_ARCH_ASE): Define.
	(EF_MIPS_ARCH_ASE_MDMX): Define.
	(EF_MIPS_ARCH_ASE_M16): Define.
	(SHF_MIPS_ADDR): Renamed SHF_MIPS_ADDR32.
	(SHF_MIPS_STRING): Renamed SHF_MIPS_ADDR64.
	(SHF_MIPS_NODUPES): Define.
	(ELF64_MIPS_R_SSYM): New MIPS ELF 64 relocation info access macro.
	(ELF64_MIPS_R_TYPE3): Likewise.
	(ELF64_MIPS_R_TYPE2): Likewise.
	(ELF64_MIPS_R_TYPE): Likewise.
	(OHW_R10KLDL): Define.