omap: mailbox: remove disable_/enable_mbox_irq in isr

No need to handle it in isr, since irq won't happen during isr.
Signed-off-by: NHiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

arch/arm/plat-omap/mailbox.c

@@ -209,8 +209,6 @@ static void __mbox_rx_interrupt(struct omap_mbox *mbox)
 	mbox_msg_t msg;
 	struct request_queue *q = mbox->rxq->queue;
 
-	disable_mbox_irq(mbox, IRQ_RX);
-
 	while (!mbox_fifo_empty(mbox)) {
 		rq = blk_get_request(q, WRITE, GFP_ATOMIC);
 		if (unlikely(!rq))
@@ -226,7 +224,6 @@ static void __mbox_rx_interrupt(struct omap_mbox *mbox)
 
 	/* no more messages in the fifo. clear IRQ source. */
 	ack_mbox_irq(mbox, IRQ_RX);
-	enable_mbox_irq(mbox, IRQ_RX);
 nomem:
 	schedule_work(&mbox->rxq->work);
 }