arm: dts: imx6ull: move input include to base device tree

The input keycode KEY_POWER is used in the imx6ull.dtsi file,
hence include the input header where used.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>

arch/arm/dts/imx6ull-14x14-evk.dts

@@ -8,7 +8,6 @@
 
 /dts-v1/;
 
-#include <dt-bindings/input/input.h>
 #include "imx6ull.dtsi"
 
 / {

arch/arm/dts/imx6ull.dtsi

@@ -8,6 +8,7 @@
 
 #include <dt-bindings/clock/imx6ul-clock.h>
 #include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include "imx6ull-pinfunc.h"
 #include "imx6ull-pinfunc-snvs.h"