arm: mvebu: define and use common Armada 370 UART pinctrl settings

This patch defines common Armada 370 pinctrl settings for uart0 and
uart1 interfaces:

 uart0: MPP0-1 as default
 uart1: MPP41-42 as default

Note: this patch has the potential to break out-of-tree users w/o
specific pinctrl settings for their uart interfaces if the default
above does not match their config.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Link: https://lkml.kernel.org/r/31412e57955c98bc9cc47b70726b5072af945cc3.1416613429.git.arno@natisbad.org


Signed-off-by: Jason Cooper <jason@lakedaemon.net>