Suppress HLSL warnings 3556 and 3571 These are both fairly common, and rarely actionable. Bug: chromium:765576 Change-Id: Ib067fcbb1d4ffe7fcd47b69dbe5defac81430a70 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2188952 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org>