The project has a strict warnings-as-errors policy. If any warnings
aren't interesting, we should disable those warnings, not
warnings-as-errors.

Change-Id: Ib3f5d21e6f368339a6af51582facdfa7508f4239
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/55609Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Nico Weber <thakis@google.com>
Tested-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>