[ARM] 4432/5: davinci: pin mux support

Support pin multiplexing configurations driver for TI DaVinci SoC

Signed-off-by: Vladimir Barinov <vbarinov@ru.mvista.com>
Acked-by: Kevin Hilman <khilman@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>