ARM: dts: imx6ul: add snvs power key support

Add i.MX6UL SNVS power key support.

Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6ul.dtsi

@@ -423,6 +423,14 @@
 					interrupts = <GIC_SPI 19 IRQ_TYPE_LEVEL_HIGH>,
 						     <GIC_SPI 20 IRQ_TYPE_LEVEL_HIGH>;
 				};
+
+				snvs_pwrkey: snvs-powerkey {
+					compatible = "fsl,sec-v4.0-pwrkey";
+					regmap = <&snvs>;
+					interrupts = <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>;
+					linux,keycode = <KEY_POWER>;
+					wakeup-source;
+				};
 			};
 
 			epit1: epit@020d0000 {