This is a reland of d7c9b31a

Original change's description:
> ppc: [liftoff] implement DropStackSlotsAndRet
>
> Change-Id: I05bcba3ad27b46b7c7888940895605ad463fc960
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3155302
> Reviewed-by: Milad Fa <mfarazma@redhat.com>
> Commit-Queue: Junliang Yan <junyan@redhat.com>
> Cr-Commit-Position: refs/heads/main@{#76774}

Change-Id: Ifced82af6fdd16c72d36493afa27f4a4824ada90
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3216041Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/main@{#77379}