Add AVX-512 detection to SkCpu, try 2.

This time, don't call xgetbv() before checking we can.

This reverts commit b26373cfd8151b2fa56bdf532ddcde4919cce09f.

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Mac-Clang-MacMini4.1-GPU-GeForce320M-x86_64-Debug

Change-Id: I148302cb36446891b1d79b2e60cde0b43420c1a8
Reviewed-on: https://skia-review.googlesource.com/9089
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
2 files changed