USB: fix previous sparse fix which was incorrect

The previous fix for a "sparse" warning in ehci_urb_dequeue() was
incorrect.  After rescheduling interrupt transfers it returned the
URB's completion status, not status for the dequeue operation itself.

This patch resolves that issue, cleans up the code in the reschedule
path, and shrinks the object code by a dozen bytes.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/ehci-hcd.c

@@ -862,18 +862,18 @@ static int ehci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 		/* reschedule QH iff another request is queued */
 		if (!list_empty (&qh->qtd_list)
 				&& HC_IS_RUNNING (hcd->state)) {
-			int schedule_status;
+			rc = qh_schedule(ehci, qh);
 
-			schedule_status = qh_schedule (ehci, qh);
-			spin_unlock_irqrestore (&ehci->lock, flags);
-
-			if (schedule_status != 0) {
-				// shouldn't happen often, but ...
-				// FIXME kill those tds' urbs
-				err ("can't reschedule qh %p, err %d",
-					qh, schedule_status);
-			}
-			return status;
+			/* An error here likely indicates handshake failure
+			 * or no space left in the schedule.  Neither fault
+			 * should happen often ...
+			 *
+			 * FIXME kill the now-dysfunctional queued urbs
+			 */
+			if (rc != 0)
+				ehci_err(ehci,
+					"can't reschedule qh %p, err %d",
+					qh, rc);
 		}
 		break;