MIPS64: Fix some features on HW.
MIPS64: Fix kFPUInvalidResult.

TEST: cctest/test-assembler-mips64/MIPS14
MIPS64: Add disassembler and macro-assembler cctests.
Merge remote-tracking branch 'mrb/mips64' into m64-gbl-mrg

Conflicts:
	Makefile
	src/cpu.cc
	src/mips64/code-stubs-mips64.cc
	tools/testrunner/local/statusfile.py
(conflicts fixed)