Remove GrPixelConfig from validateSurfaceParams

This wasn't even used...

Bug: skia:6718
Change-Id: I6543fd11b1f0d9136088fda8c6962aebc16ae5cb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/264858
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
5 files changed