Also remove some ifdefs since it is implemented on all architectures.

Bug: v8:10997
Change-Id: I06f82e2c67219a8990bdd7c78e63b1300c8f34d2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2620907Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72024}