update common.mk This includes updated LFS flags. BUG=chromium:464024 TEST=precq passes Change-Id: I9c0f3b22885ddabaa36b3e85290b7f9bd2989272 Reviewed-on: https://chromium-review.googlesource.com/262674 Reviewed-by: Daniel Ehrenberg <[email protected]> Tested-by: Mike Frysinger <[email protected]> Commit-Queue: Mike Frysinger <[email protected]>