USB OHCI controllers

Required properties:
- compatible : "generic-ohci"
- reg : ohci controller register range (address and length)
- interrupts : ohci controller interrupt

Optional properties:
- big-endian-regs : boolean, set this for hcds with big-endian registers
- big-endian-desc : boolean, set this for hcds with big-endian descriptors
- big-endian : boolean, for hcds with big-endian-regs + big-endian-desc
- no-big-frame-no : boolean, set if frame_no lives in bits [15:0] of HCCA
- remote-wakeup-connected: remote wakeup is wired on the platform
- num-ports : u32, to override the detected port count
- clocks : a list of phandle + clock specifier pairs. In case of Renesas
	   R-Car Gen3 SoCs:
	   - if a host only channel: first clock should be host.
	   - if a USB DRD channel: first clock should be host and second one
				   should be peripheral.
- phys : see usb-hcd.txt in the current directory
- resets : a list of phandle + reset specifier pairs

additionally the properties from usb-hcd.txt (in the current directory) are
supported.

Example:

	ohci0: usb@1c14400 {
		compatible = "allwinner,sun4i-a10-ohci", "generic-ohci";
		reg = <0x01c14400 0x100>;
		interrupts = <64>;
		clocks = <&usb_clk 6>, <&ahb_gates 2>;
		phys = <&usbphy 1>;
		phy-names = "usb";
	};
