gcc:
	* config.gcc: Removed mips-sgi-irix5*, mips-sgi-irix6.[0-4]* from
	list of obsolete configurations.
	Disabled check for obsolete configurations.
	(mips-sgi-irix[56]*): Restrict to mips-sgi-irix6.5*.
	Removed support for previous versions.
	* config/mips/iris.h: Removed.
	* config/mips/iris5.h: Removed.
	* config/mips/iris6.h: Merged old iris.h contents.
	(TARGET_IRIX): Removed.
	(DRIVER_SELF_SPECS): Removed mabi=32.
	(IDENT_ASM_OP): Removed undef.
	(STARTFILE_SPEC): Removed mabi=32.
	(ENDFILE_SPEC): Likewise.
	(IRIX_SUBTARGET_LINK_SPEC): Likewise.
	(MACHINE_TYPE): Update for IRIX 6.5.
	* config/mips/mips.c (mips_build_builtin_va_list): Replaced
	TARGET_IRIX by TARGET_IRIX6.
	(mips_file_start): Likewise.
	(mips_output_external): Remove IRIX 5/6 O32 support.
	(mips_output_function_prologue): Likewise.
	* config/mips/mips.h (TARGET_GPWORD): Replaced TARGET_IRIX by
	TARGET_IRIX6.
	(TARGET_CPU_CPP_BUILTINS): Likewise.
	(TARGET_IRIX): Removed.
	* config/mips/t-iris6 (MULTILIB_OPTIONS): Removed mabi=32.
	(MULTILIB_DIRNAMES): Removed 32.
	(MULTILIB_OSDIRNAMES): Removed ../lib.
	* doc/install.texi (Prerequisites): Don't reference IRIX before
	6.5.
	(Specific, mips-sgi-irix5): Document removal.
	(Specific, mips-sgi-irix6): Document IRIX 6.[0-4] and O32 ABI
	removal.
	Remove references to older IRIX 6 releases and the O32 ABI.

	gcc/ada:
	* gcc-interface/Makefile.in: Removed mips-sgi-irix5* support.

	libstdc++-v3:
	* configure.host: Removed irix[1-6], irix[1-5].*, irix6.[0-4]*
	support.
	* config/os/irix/irix5.2: Removed.

From-SVN: r159121