ARM: mx28: add gpmi-nand support

add gpmi-nand device tree support.
add gpmi-nand pinctrl support.

Also enable the gpmi support for mx28-evk board.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/boot/dts/imx28-evk.dts b/arch/arm/boot/dts/imx28-evk.dts
index ee520a5..e53cf67 100644
--- a/arch/arm/boot/dts/imx28-evk.dts
+++ b/arch/arm/boot/dts/imx28-evk.dts
@@ -22,6 +22,12 @@
 
 	apb@80000000 {
 		apbh@80000000 {
+			gpmi-nand@8000c000 {
+				pinctrl-names = "default";
+				pinctrl-0 = <&gpmi_pins_a &gpmi_status_cfg>;
+				status = "okay";
+			};
+
 			ssp0: ssp@80010000 {
 				compatible = "fsl,imx28-mmc";
 				pinctrl-names = "default";