When result is returned in a register to the calling code, some GCC
versions use 32 bit compare, and some use 64 bit compare. In the case
comparison is 64 bit, GCC on PPC64 arch is expecting the return value to
be sign-extended, leading to an error in comparison.

Change-Id: I05b7e1566bc9bb931ce9998bb310eb29c50e90e4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2968449Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Vasili Skurydzin <vasili.skurydzin@ibm.com>
Cr-Commit-Position: refs/heads/master@{#75245}