Metal: Support NV_shader_noperspective_interpolation Fixed: angleproject:8095 Change-Id: Ieded1f704f82963984f1aee5072f152de0de374c Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4368473 Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com> Reviewed-by: Geoff Lang <geofflang@chromium.org>