Also add missing msl macros to the renamer.
Bug: tint:951
Change-Id: I543e6eae885c979596ca63f9d6c7378dd5425e8a
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/56941
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@chromium.org>
Auto-Submit: Ben Clayton <bclayton@google.com>
Reviewed-by: James Price <jrprice@google.com>