ppc: Unify Memory Operation 3

Clean up 32 bit Load/Store

Change-Id: I5bab0d33830039d3c4a501eba6e7cf95f4b9559e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2933597


Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/master@{#74927}