GBB: Add missing flag LID_SHUTDOWN to vb2_gbb_flag structure BUG=None BRANCH=None TEST=Compiles successfully Change-Id: I80a501efc3940ca5657dc143c0ab3c6b020dc1e0 Signed-off-by: Furquan Shaikh <[email protected]> Reviewed-on: https://chromium-review.googlesource.com/271620 Trybot-Ready: Furquan Shaikh <[email protected]> Tested-by: Furquan Shaikh <[email protected]> Reviewed-by: Aaron Durbin <[email protected]> Commit-Queue: Furquan Shaikh <[email protected]>