This was added to try and skip tests when run on platforms without
sse41, but it doesn't work fuzz tests, since they add the flags on
command line. With https://crrev.com/c/2389982 we are now adding the
flag in the js test file itself.

Remove this condition since it's likely to be confusing and not work
correctly for all tests.

Bug: v8:10863
Change-Id: Ieeadade05dfc04ce250710d09a6a272775ce98c9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2391321Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69685}