iris6.h (ENDFILE_SPEC): Use crtfastmath.o if -ffast-math etc.

iris6.h (ENDFILE_SPEC): Use crtfastmath.o if -ffast-math etc.

	gcc:
	* config/mips/iris6.h (ENDFILE_SPEC): Use crtfastmath.o if
	-ffast-math etc.

	libgcc:
	* config.host (mips-sgi-irix6.5*): Add t-crtfm to tmake_file.
	Add crtfastmath.o to extra_parts.
	(mips64*-*-linux*, mips*-*-linux*): Use t-crtfm instead of
	mips/t-crtfm.
	* config/mips/t-crtfm: Remove.

From-SVN: r174686