OMAP4: Keyboard: Mux changes in the board file

The mux settings for keypad  are done for omap4430sdp in
board file.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
[tony@atomide.com: improved formatting a bit]
Signed-off-by: Tony Lindgren <tony@atomide.com>