arm64: dts: qcom: msm8939-asus-z00t: add labels for gpio-keys

Since there are now two devices using "gpio-keys" compatible, this
commit adds labels to them, so it is possible to distinguish between them.

Signed-off-by: Erikas Bitovtas <[email protected]>

Author: erikas9987

arch/arm64/boot/dts/qcom/msm8939-asus-z00t.dts

@@ -67,6 +67,8 @@
 		pinctrl-0 = <&gpio_keys_default>;
 		pinctrl-names = "default";
 
+		label = "GPIO Buttons";
+
 		button-volume-up {
 			label = "Volume Up";
 			gpios = <&tlmm 107 GPIO_ACTIVE_LOW>;