ARM: i.MX6 Sabrelite: add missing of_machine_is_compatible checks

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
scripts: kwbimage: fix imagebuild on 32bit host system

We have to use strtoul to run the tool working on 32bit systems.
Otherwise it will generate signed numbers for strings representing
values with the 32nd bit set.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>