[PATCH v6] MXC: mx21ads base support

Base machine support for the  Freescale i.MX21ADS
(M9328MX21ADSE) Application Development System.
Signed-off-by: Ivo Clarysse <ivo.clarysse@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>