This was only relevant for the br_on_exn instruction, which doesn't
exist anymore.

R=clemensb@chromium.org

Change-Id: I03f85a316a8265ad1c5e1c15862d7ae98b784977
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2902734Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74641}