The CL introduces optimizations in code generator to MipsTst, MipsCmp,
MipsCmpS and MipsCmpD instructions for mips32 and Mips64Tst, Mips64Cmp,
Mips64CmpS and Mips64CmpD for mips64.

BUG=

Change-Id: I6daf465e0ac7475691078b4d683da5247df6ea99
Reviewed-on: https://chromium-review.googlesource.com/584529Reviewed-by: Ivica Bogosavljevic <ivica.bogosavljevic@imgtec.com>
Commit-Queue: Miran Karić <Miran.Karic@imgtec.com>
Cr-Commit-Position: refs/heads/master@{#46892}