USB: xhci: Root hub support.

Add functionality for getting port status and hub descriptor for xHCI root
hubs.  This is WIP because the USB 3.0 hub descriptor is different from
the USB 2.0 hub descriptor.  For now, we lie about the root hub descriptor
because the changes won't effect how the core talks to the root hub.
Later we will need to add the USB 3.0 hub descriptor for real hubs, and
this code might change.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
index a99c119..d7c2fed 100644
--- a/drivers/usb/host/xhci-hcd.c
+++ b/drivers/usb/host/xhci-hcd.c
@@ -349,6 +349,9 @@
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 	void (*doorbell)(struct xhci_hcd *) = NULL;
 
+	hcd->uses_new_polling = 1;
+	hcd->poll_rh = 0;
+
 	xhci_dbg(xhci, "xhci_run\n");
 #if 0	/* FIXME: MSI not setup yet */
 	/* Do this at the very last minute */