This cl uses the newly added instructions on power10 for
extracting the sign bits.

Change-Id: I9e4fa3bdd7fa5fc7004695c1d3ac29e3906d5207
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3056506Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#75947}