On PPC we don't have the nearest int FP roundings available,
bailing out to C runtime.

Change-Id: I4d8ee4ba74fb6c60752cdbde4a73052ab159821a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3913247Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/main@{#83399}