The CL adds optimizations for Neg_s and Neg_d macro instructions.

BUG=

Change-Id: I842480ac3195860a1a36dadcffb5dc560ca8f424
Reviewed-on: https://chromium-review.googlesource.com/555131Reviewed-by: Ivica Bogosavljevic <ivica.bogosavljevic@imgtec.com>
Commit-Queue: Miran Karić <Miran.Karic@imgtec.com>
Cr-Commit-Position: refs/heads/master@{#46340}