Samsung Exynos SoC USB controller

The device node for USB controller for Samsung SOC have
following properties

OHCI
Required properties:
 - compatible: should be "samsung,exynos-ohci" for USB 2.0
   OHCI companion controller in host mode.
 - reg: physical base address of the controller and length
   of memory mapped.
 - interrupts: interrupt number to the cpu.

ohci {
	compatible = "samsung,exynos-ohci";
	reg = <0x12120000 0x100>;
	interrupts = <0 71 0>;
};

EHCI
Required properties:
 - compatible:	should be "samsung,exynos-ehci" for USB 2.0
   EHCI controller in host mode.
 - reg: physical base address of the controller and length
   of memory mapped.
 - interrupts: interrupt number to the cpu.

Optional properties:
 - samsung,vbus-gpio:  if present, specifies the GPIO
   that needs to be pulled up for the bus to be powered.

ehci {
	compatible = "samsung,exynos-ehci";
	reg = <0x12110000 0x100>;
	interrupts = <0 71 0>;
};

ehci {
	samsung,vbus-gpio = <&gpx2 6 1 3 3>;
};

