ARM: tqma53: change uart to second uart

The second UART is used on the mba53 baseboard. The first UART is only
used on custom hardware. This patch changes the UART to the one used
on the freely available baseboard.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Release v2013.04.0

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>