Patch from Sascha Hauer

Fix PD7_AF_UART2_DTR definition
Signed-off-by: NGiancarlo Formicuccia <gformicuccia@atinno.com>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>