WIP: ARM: tegra: surface-rt: configure windows button as a wake up source

Configure windows button to wake up device from suspend.

Signed-off-by: Anton Bambura <jenneron@protonmail.com>

Author: jenneron

arch/arm/boot/dts/tegra30-microsoft-surface-rt.dts

@@ -259,6 +259,7 @@
 			gpios = <&gpio TEGRA_GPIO(S, 5) GPIO_ACTIVE_HIGH>;
 			linux,code = <KEY_LEFTMETA>;
 			debounce-interval = <10>;
+			wakeup-source;
 		};
 
 		volume-down {