Change the has-optimized FeedbackVector bit to two bits, one for Maglev
and one for Turbofan. Ignition and Sparkplug can check both bits, while
Maglev will only check the Turbofan one.

Bug: v8:7700
Change-Id: I95f6e4326180cac02f127a97438f960950f09d82
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3856569
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82748}