arm64: zynqmp: Fix gpio-key DT description

All gpio-key descriptionos with dt-schema.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/a67884f4fad98b94198123eef45ffdad511b0dc6.1709887234.git.michal.simek@amd.com
diff --git a/arch/arm/dts/zynqmp-zcu208-revA.dts b/arch/arm/dts/zynqmp-zcu208-revA.dts
index b4e2474..a113e47 100644
--- a/arch/arm/dts/zynqmp-zcu208-revA.dts
+++ b/arch/arm/dts/zynqmp-zcu208-revA.dts
@@ -46,7 +46,7 @@
 	gpio-keys {
 		compatible = "gpio-keys";
 		autorepeat;
-		sw19 {
+		switch-19 {
 			label = "sw19";
 			gpios = <&gpio 22 GPIO_ACTIVE_HIGH>;
 			linux,code = <KEY_DOWN>;