MIPS[64] big endian doesn't have LiftOff implementation yet.
This CL skips offending tests.

Change-Id: I75797f2f234bbcafc535f3ff97670acabc32e216
Reviewed-on: https://chromium-review.googlesource.com/951486Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Cr-Commit-Position: refs/heads/master@{#51782}