This adds a fairly simple xhci-platform driver support. Currently it is
used by the dwc3 driver for supporting host mode.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>