ARM: dts: imx: Add imx51 KPP entry

1) Add KPP device node entry.
2) Add one KPP pinctrl entry.
Signed-off-by: NLiu Ying <Ying.Liu@freescale.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

arch/arm/boot/dts/imx51.dtsi

@@ -221,6 +221,14 @@
 				#interrupt-cells = <2>;
 			};
 
+			kpp: kpp@73f94000 {
+				compatible = "fsl,imx51-kpp", "fsl,imx21-kpp";
+				reg = <0x73f94000 0x4000>;
+				interrupts = <60>;
+				clocks = <&clks 0>;
+				status = "disabled";
+			};
+
 			wdog1: wdog@73f98000 {
 				compatible = "fsl,imx51-wdt", "fsl,imx21-wdt";
 				reg = <0x73f98000 0x4000>;
@@ -410,6 +418,21 @@
 						>;
 					};
 				};
+
+				kpp {
+					pinctrl_kpp_1: kppgrp-1 {
+						fsl,pins = <
+							438 0xe0	/* MX51_PAD_KEY_ROW0__KEY_ROW0 */
+							439 0xe0	/* MX51_PAD_KEY_ROW1__KEY_ROW1 */
+							440 0xe0	/* MX51_PAD_KEY_ROW2__KEY_ROW2 */
+							441 0xe0	/* MX51_PAD_KEY_ROW3__KEY_ROW3 */
+							442 0xe8	/* MX51_PAD_KEY_COL0__KEY_COL0 */
+							444 0xe8	/* MX51_PAD_KEY_COL1__KEY_COL1 */
+							446 0xe8	/* MX51_PAD_KEY_COL2__KEY_COL2 */
+							448 0xe8	/* MX51_PAD_KEY_COL3__KEY_COL3 */
+						>;
+					};
+				};
 			};
 
 			pwm1: pwm@73fb4000 {