mksnapshot is compiled/ran in the host configuration (usually x64), we
need to propagate the flag (using bazel transitions) to tell mksnapshot
to generate code to a different architecture.

No-Try: true
Change-Id: I5923f5895872a8cbf2982925a545855a330c51fd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3306568
Auto-Submit: Victor Gomes <victorgomes@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78177}