arm64: dts: m3ulcb: enable GPIO keys

This supports GPIO keys on M3ULCB board
Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/r8a7796-m3ulcb.dts

@@ -12,6 +12,7 @@
 /dts-v1/;
 #include "r8a7796.dtsi"
 #include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
 
 / {
 	model = "Renesas M3ULCB board based on r8a7796";
@@ -41,6 +42,18 @@ led6 {
 			gpios = <&gpio6 13 GPIO_ACTIVE_HIGH>;
 		};
 	};
+
+	keyboard {
+		compatible = "gpio-keys";
+
+		key-1 {
+			linux,code = <KEY_1>;
+			label = "SW3";
+			wakeup-source;
+			debounce-interval = <20>;
+			gpios = <&gpio6 11 GPIO_ACTIVE_LOW>;
+		};
+	};
 };
 
 &extal_clk {