Explicitly #include climits header for CHAR_BIT.

Bug: v8:12691
Change-Id: I9d7a28543883a5387e006c4b6ee4491243a06207
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3516925
Auto-Submit: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79446}