ARM: zynq: Add reset-gpio property for USB on Zybo

DTS syncup with Linux kernel.
Add missing reset-gpio property.

Signed-off-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/arm/dts/zynq-zybo.dts

@@ -31,8 +31,9 @@
 	};
 
 	usb_phy0: phy0 {
-		compatible = "usb-nop-xceiv";
 		#phy-cells = <0>;
+		compatible = "usb-nop-xceiv";
+		reset-gpios = <&gpio0 46 1>;
 	};
 };