Access to some of the OMAP4 GPIO registers are not properly handled.
This patch fixes it.

This patch is tested on 3430SDP and 4430SDP boards
Signed-off-by: Charulatha V <charu@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>