zero extending the offset register must happen regardless
of the length of the offset_imm.

We can only use ip as the offset_reg as r0 and and r1
are being used as scratch later on.

Change-Id: I5517f974af40eb014b8e1f58f8e531909c4d466a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3794646
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Reviewed-by: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/main@{#82087}