mttools: update to _FORTIFY_SOURCE=3

Since this project explicitly specifies its FORTIFY level, update it to
the level CrOS wants to move to. This isn't _removed_, since it's copied
from a template file, and consistency with that seems useful.

BUG=b:288411201
TEST=CQ+1

Change-Id: Ia1ba7eb0ac8e37f493b3a0dcaf3ecee526124a04
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/mttools/+/4707932
Commit-Queue: George Burgess <gbiv@chromium.org>
Reviewed-by: Henry Barnor <hbarnor@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>
1 file changed