xhci: Rename variables related to transfer descritpors

urb_priv structure has a count on how many TDs the
URB contains, and how many of those TD's we have handled.

rename:
length -> num_tds
td_cnt -> num_tds_done

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 40b1486..bee6272 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1379,8 +1379,8 @@
 		buffer++;
 	}
 
-	urb_priv->length = num_tds;
-	urb_priv->td_cnt = 0;
+	urb_priv->num_tds = num_tds;
+	urb_priv->num_tds_done = 0;
 	urb->hcpriv = urb_priv;
 
 	trace_xhci_urb_enqueue(urb);
@@ -1523,8 +1523,8 @@
 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 				"HW died, freeing TD.");
 		urb_priv = urb->hcpriv;
-		for (i = urb_priv->td_cnt;
-		     i < urb_priv->length && xhci->devs[urb->dev->slot_id];
+		for (i = urb_priv->num_tds_done;
+		     i < urb_priv->num_tds && xhci->devs[urb->dev->slot_id];
 		     i++) {
 			td = urb_priv->td[i];
 			if (!list_empty(&td->td_list))
@@ -1549,8 +1549,8 @@
 	}
 
 	urb_priv = urb->hcpriv;
-	i = urb_priv->td_cnt;
-	if (i < urb_priv->length)
+	i = urb_priv->num_tds_done;
+	if (i < urb_priv->num_tds)
 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 				"Cancel URB %p, dev %s, ep 0x%x, "
 				"starting at offset 0x%llx",
@@ -1560,7 +1560,7 @@
 					urb_priv->td[i]->start_seg,
 					urb_priv->td[i]->first_trb));
 
-	for (; i < urb_priv->length; i++) {
+	for (; i < urb_priv->num_tds; i++) {
 		td = urb_priv->td[i];
 		list_add_tail(&td->cancelled_td_list, &ep->cancelled_td_list);
 	}