dt-bindings: usb: Add usb-phy property to the jz4740-musb node

Add a required 'usb-phy' property, to obtain a phandle to the USB PHY
from devicetree.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/usb/ingenic,jz4740-musb.txt

@@ -8,9 +8,15 @@ Required properties:
 - interrupt-names: must be "mc"
 - clocks: phandle to the "udc" clock
 - clock-names: must be "udc"
+- phys: phandle to the USB PHY
 
 Example:
 
+usb_phy: usb-phy@0 {
+	compatible = "usb-nop-xceiv";
+	#phy-cells = <0>;
+};
+
 udc: usb@13040000 {
 	compatible = "ingenic,jz4740-musb";
 	reg = <0x13040000 0x10000>;
@@ -21,4 +27,6 @@ udc: usb@13040000 {
 
 	clocks = <&cgu JZ4740_CLK_UDC>;
 	clock-names = "udc";
+
+	phys = <&usb_phy>;
 };