nvidia-cbootimage: add submodule

Change-Id: I3ad8eed42255db426987065190c197baead40673
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6836
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2 files changed