MUSB: Blackfin: don't fake blackfin_interrupt() result

Commit a5073b52833e4df8e16c93dc4cbb7e0c558c74a2 (musb_gadget: fix unhandled
endpoint 0 IRQs) misses this change to blackfin.c: stop faking successful
result of blackfin_interrupt() and emitting a debug message on an unhandled
interrupt.

Signed-off-by: Sergei Shtylyov <sshtylyov@mvista.com>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/musb/blackfin.c

@@ -172,13 +172,7 @@ static irqreturn_t blackfin_interrupt(int irq, void *__hci)
 
 	spin_unlock_irqrestore(&musb->lock, flags);
 
-	/* REVISIT we sometimes get spurious IRQs on g_ep0
-	 * not clear why... fall in BF54x too.
-	 */
-	if (retval != IRQ_HANDLED)
-		DBG(5, "spurious?\n");
-
-	return IRQ_HANDLED;
+	return retval;
 }
 
 static void musb_conn_timer_handler(unsigned long _musb)