Update compressed texturing GM

This CL has some extra headroom for upcoming kBC1_RGBA8_UNORM support.

Bug: skia:9680
Change-Id: I866c7fe12657a41575c57dcd001a6a09477fc44a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/264096
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
5 files changed