Instead of invoking both the generational and marking barrier
explicitly, we can just invoke the combined barrier which does both
for us.

Also we simply use the full write barrier for all writes in the deserializer. While we could avoid the generational barrier in a few
cases, this only costs us a single predictable untaken branch without
an additional load.

Bug: v8:11708
Change-Id: Iebd0af06efe42a3ac4e5725131362600ab16bc7a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3662900
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80712}