smegw01: Add altbootcmd

Add an altbootcmd script, which is convenient way to integrate with
swupdate and perform a roll back of the previous working version in the
case of update failure.

Signed-off-by: Eduard Strehlau <eduard@lionizers.com>
Signed-off-by: Fabio Estevam <festevam@denx.de>
2 files changed