Add SSE2 and SSE4.1 limited builds.

As the machines we test on get fancier and fancier, we're losing
coverage of older instruction sets.  This adds a flag to skip
CPU detection, and two new builds to test SSE2 and SSE4.1.

Change-Id: Ie28518b30860f90c80f71020e64e3696a7047021
Reviewed-on: https://skia-review.googlesource.com/c/skcms/+/213849
Commit-Queue: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
4 files changed