s390x: [liftoff] implement AtomicSub

Change-Id: Id5dd7a33b4d64cb73ccc4f5c1457f8a28905d814
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2810885


Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/master@{#73845}