opcodes are already defined under the instruction-selector.

Change-Id: Ib8cc1d3b7d8e3f1725306b12450f43c2aff1ae83
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3616722Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80284}