ARM: dts: am43xx-epos-evm: Add matrix keypad as wakeup source

Mark matrix-keypad as a wakeup source.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am43x-epos-evm.dts

@@ -80,6 +80,7 @@ matrix_keypad: matrix_keypad0 {
 		pinctrl-names = "default", "sleep";
 		pinctrl-0 = <&matrix_keypad_default>;
 		pinctrl-1 = <&matrix_keypad_sleep>;
+		wakeup-source;
 
 		row-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH		/* Bank0, pin12 */
 			     &gpio0 13 GPIO_ACTIVE_HIGH		/* Bank0, pin13 */