Added if statements to check if VECTOR_FACILITY are supported in order to avoid “illegal instruction” errors during SIMD tests on old s390 machines.

Change-Id: I1ab841db02e6c47de54d4a15b973e5366f88e117
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1704937Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#62852}