This extends the idea already used by "MaterializeMergedConstants":
certain values have to be processed by every br*, so to protect against
cascades of conditional jumps causing lots of repeated work, it makes
sense to do such processing just once.
For the module in the linked bug, this reduces Liftoff generated code
size from 69MB to 181KB.

Fixed: v8:13072
Change-Id: Ie9f98240e93751988067d4774d4a09b2b39bdad6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3760444Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81722}