Add a uuu script that flashes the full-boot-image.

u-boot-builder can generate a "full-boot-image" that contains an
m4.img and an imx u-boot.

Signed-off-by: Angus Ainslie <angus@akkea.ca>
4 jobs for full-boot-image in 3 minutes and 30 seconds (queued for 2 seconds)