Just to ensure this is portable across all platforms.

Credits go to https://github.com/graphitemaster/incbin, bits of the
.incbin code were taken from there. Thanks!

Bug: v8:6666
Change-Id: Id068f70fb4ac925b574a14dec40cf80627a22073
Reviewed-on: https://chromium-review.googlesource.com/881181
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50883}