ARM: dts: imx50: Add PHY node for usbotg and adjust clocks

Even though the ChipIdea USB controller binding[1] doesn't specify the
properties that reference a PHY as required, the Linux driver
requires[2] such a reference.

The clock situation is like on i.MX53: The USB controller is clocked
from IMX5_CLK_USBOH3_GATE and the PHY from IMX5_CLK_USB_PHY1_GATE.

[1]: Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt
[2]: Search for EINVAL in drivers/usb/chipidea/ci_hdrc_imx.c
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx50.dtsi

@@ -86,6 +86,14 @@ osc {
 		};
 	};
 
+	usbphy0: usbphy-0 {
+		compatible = "usb-nop-xceiv";
+		clocks = <&clks IMX5_CLK_USB_PHY1_GATE>;
+		clock-names = "main_clk";
+		#phy-cells = <0>;
+		status = "okay";
+	};
+
 	soc {
 		#address-cells = <1>;
 		#size-cells = <1>;
@@ -197,7 +205,8 @@ usbotg: usb@53f80000 {
 				compatible = "fsl,imx50-usb", "fsl,imx27-usb";
 				reg = <0x53f80000 0x0200>;
 				interrupts = <18>;
-				clocks = <&clks IMX5_CLK_USB_PHY1_GATE>;
+				clocks = <&clks IMX5_CLK_USBOH3_GATE>;
+				fsl,usbphy = <&usbphy0>;
 				status = "disabled";
 			};