Rel/acq is needed to guarantee the memcpy for re-embedding builtins
should be visible to all threads once embedded_blob_code_copy_ is
observed to have the address of the copy.

Bug: v8:11460
Change-Id: I68d0c532b7c7bba3d2cafeb0ff83533a67a1447d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2890590Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Auto-Submit: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74529}