ARM: dts: rockchip: enable usbphy on rk3288-firefly

Enable the usb phys on the firefly board.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk3288-firefly.dtsi

@@ -459,6 +459,10 @@ &uart3 {
 	status = "okay";
 };
 
+&usbphy {
+	status = "okay";
+};
+
 &usb_host1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&usbhub_rst>;