Adds support for I32x4Splat, I32x4ExtractLane, I32x4ReplaceLane,
I32x4Add, I32x4Sub, S128Zero operations for mips32 and mips64
architectures.

BUG=

Note: Depends on patch: https://codereview.chromium.org/2740123004/
Review-Url: https://codereview.chromium.org/2753903004
Cr-Commit-Position: refs/heads/master@{#44326}