staging: mt7621-dts: convert to gpio-keys

Now that gpio-interrupts work correctly, we
can use gpio-keys instead of gpio-keys-polled
for the single push-button on the gbpc-1.
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-dts/gbpc1.dts

@@ -24,11 +24,8 @@ i2c@900 {
 		};
 	};
 
-	gpio-keys-polled {
-		compatible = "gpio-keys-polled";
-		#address-cells = <1>;
-		#size-cells = <0>;
-		poll-interval = <20>;
+	gpio-keys {
+		compatible = "gpio-keys";
 
 		reset {
 			label = "reset";