Update SolidRun iMX6 platforms DT descriptions to be dual-licensed.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Acked-by: NRabeeh Khoury <rabeeh@solid-run.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>