ARM: dts: Add max77686 RTC interrupt to cros5250-common

Without the interrupt you'll get problems if you enable
CONFIG_RTC_DRV_MAX77686.  Setup the interrupt properly in the device
tree.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: stable@vger.kernel.org

arch/arm/boot/dts/cros5250-common.dtsi

@@ -27,6 +27,13 @@ pinctrl@11400000 {
 		i2c2_bus: i2c2-bus {
 			samsung,pin-pud = <0>;
 		};
+
+		max77686_irq: max77686-irq {
+			samsung,pins = "gpx3-2";
+			samsung,pin-function = <0>;
+			samsung,pin-pud = <0>;
+			samsung,pin-drv = <0>;
+		};
 	};
 
 	i2c@12C60000 {
@@ -35,6 +42,11 @@ i2c@12C60000 {
 
 		max77686@09 {
 			compatible = "maxim,max77686";
+			interrupt-parent = <&gpx3>;
+			interrupts = <2 0>;
+			pinctrl-names = "default";
+			pinctrl-0 = <&max77686_irq>;
+			wakeup-source;
 			reg = <0x09>;
 
 			voltage-regulators {