This CL adds const-eval for the `ceil` builtin
Bug: tint:1581
Change-Id: I32957d17000df1a8a59ce37f49b6177d1087406c
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/108342
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>