Based on the updates to spec at
https://github.com/WebAssembly/simd/pull/89

Change-Id: Ie60037e4de7a6953708a98c708afc9a820e6aa97
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728347Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63034}