ld: Add missing eelf32mbel_linux.c to ALL_EMULATION_SOURCES.

ld:
	* Makefile.am (ALL_EMULATION_SOURCES): Add missing eelf32mbel_linux.c.
	* Makefile.in: Regenerate.
Mark MSA as requiring FP64

gas/
	* config/tc-mips.c (FP64_ASES): Add ASE_MSA.
	(mips_after_parse_args): Do not select ASE_MSA without -mfp64.

gas/testsuite/

	* gas/mips/micromips@msa-branch.d: Rework expected output for fp64.
	* gas/mips/msa-branch.d: Likewise.