USB Peripheral Controller driver for Aeroflex Gaisler GRUSBDC.

The GRUSBDC USB Device Controller core is available in the GRLIB VHDL
IP core library.

Note: In the ordinary environment for the core, a Leon SPARC system,
these properties are built from information in the AMBA plug&play.

Required properties:

- name : Should be "GAISLER_USBDC" or "01_021"

- reg : Address and length of the register set for the device

- interrupts : Interrupt numbers for this device. Either one interrupt number
	for all interrupts, or one for status related interrupts, one for IN
	endpoint related interrupts and one for OUT endpoint related interrupts.

Optional properties:

- epobufsizes : Array of buffer sizes for OUT endpoints when they differ
	from the default size of 1024. The array is indexed by the OUT endpoint
	number. If the property is present it typically contains one entry for
	each OUT endpoint of the core. Fewer entries overrides the default sizes
	only for as many endpoints as the array contains.

- epibufsizes : Array of buffer sizes for IN endpoints when they differ
	from the default size of 1024. The array is indexed by the IN endpoint
	number. If the property is present it typically contains one entry for
	each IN endpoint of the core. Fewer entries overrides the default sizes
	only for as many endpoints as the array contains.

For further information look in the documentation for the GLIB IP core library:
http://www.gaisler.com/products/grlib/grip.pdf
