Patch from Sascha Hauer

This patch adds the serial driver for Hilscher's netX network
processors.
Signed-off-by: NRobert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>