The fuzzers picked up this flag, and are now complaining that they run
into UNREACHABLE/FATAL too often because the {PerfJitLogger} is not
implemented on non-linux platforms.
This CL removes the flag if it's not supported, so users get a warning
about the unknown flag, but otherwise it's ignored. This should unblock
the fuzzers, and slightly reduces binary size on non-linux.

R=ahaas@chromium.org

Bug: chromium:1035233
Change-Id: I6b9282318bc82ff23173bc83ae31cb2d8cbdcdb7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1993969
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65695}