ARM: dts: omap3-gta04: make use of input event include file and constants

we can replace magic numbers by symbolic constants now.
Signed-off-by: NH. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

arch/arm/boot/dts/omap3-gta04.dtsi

@@ -10,6 +10,7 @@
 /dts-v1/;
 
 #include "omap36xx.dtsi"
+#include <dt-bindings/input/input.h>
 
 / {
 	model = "OMAP3 GTA04";
@@ -43,7 +44,7 @@
 
 		aux-button {
 			label = "aux";
-			linux,code = <169>;
+			linux,code = <KEY_PHONE>;
 			gpios = <&gpio1 7 GPIO_ACTIVE_HIGH>;
 			wakeup-source;
 		};