ARM: dts: TWL4030: Add power button support

Enable support for the power button.
Signed-off-by: NSebastian Reichel <sre@debian.org>
Signed-off-by: NBenoit Cousson <bcousson@baylibre.com>

arch/arm/boot/dts/twl4030.dtsi

@@ -133,4 +133,9 @@
 		compatible = "ti,twl4030-pwmled";
 		#pwm-cells = <2>;
 	};
+
+	twl_pwrbutton: pwrbutton {
+		compatible = "ti,twl4030-pwrbutton";
+		interrupts = <8>;
+	};
 };