ARM: dts: imx25-pinfunc: add all UART mux modes

Apart from a few additions this also contains two fixes where the daisy
chain input selection register was missing. Moreover dropped _MUX from
some pins for consistency.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>