ARM: dts: omap: Add missing #phy-cells to usb-nop-xceiv

"usb-nop-xceiv" is using the phy binding, but is missing #phy-cells
property. This is probably because the binding was the precursor to the phy
binding.

Fixes the following warning in OMAP dts files:

Warning (phys_property): Missing property '#phy-cells' in node ...

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: "BenoƮt Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Enric Balletbo i Serra <eballetbo@gmail.com>
Cc: Javier Martinez Canillas <javier@dowhile0.org>
Cc: linux-omap@vger.kernel.org
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/boot/dts/omap3-beagle.dts b/arch/arm/boot/dts/omap3-beagle.dts
index 4d2eaf8..3ca8991 100644
--- a/arch/arm/boot/dts/omap3-beagle.dts
+++ b/arch/arm/boot/dts/omap3-beagle.dts
@@ -64,6 +64,7 @@
 		compatible = "usb-nop-xceiv";
 		reset-gpios = <&gpio5 19 GPIO_ACTIVE_LOW>;	/* gpio_147 */
 		vcc-supply = <&hsusb2_power>;
+		#phy-cells = <0>;
 	};
 
 	sound {