If test webkit/dfg-int-overflow-in-loop is executed with option --noopt,
execution will be too slow on simulator. Therefore, this test will be
skipped on MIPS64 simulators.

TEST=webkit/dfg-int-overflow-in-loop
BUG=

Change-Id: I3d116fe579a5690c817a9a9d4e8a4bf8188298cc
Reviewed-on: https://chromium-review.googlesource.com/951610
Commit-Queue: Ilija Pavlović <ilija.pavlovic@mips.com>
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51785}