atm: firestream: fix interruptible_sleep_on race

interruptible_sleep_on is racy and going away. This replaces the one use
in the firestream driver with the appropriate wait_event_interruptible
variant.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Chas Williams <chas@cmf.nrl.navy.mil>
Cc: linux-atm-general@lists.sourceforge.net
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/atm/firestream.c

@@ -736,8 +736,8 @@ static void process_txdone_queue (struct fs_dev *dev, struct queue *q)
       
 			skb = td->skb;
 			if (skb == FS_VCC (ATM_SKB(skb)->vcc)->last_skb) {
-				wake_up_interruptible (& FS_VCC (ATM_SKB(skb)->vcc)->close_wait);
 				FS_VCC (ATM_SKB(skb)->vcc)->last_skb = NULL;
+				wake_up_interruptible (& FS_VCC (ATM_SKB(skb)->vcc)->close_wait);
 			}
 			td->dev->ntxpckts--;
 
@@ -1123,7 +1123,7 @@ static void fs_close(struct atm_vcc *atm_vcc)
 		   this sleep_on, we'll lose any reference to these packets. Memory leak!
 		   On the other hand, it's awfully convenient that we can abort a "close" that
 		   is taking too long. Maybe just use non-interruptible sleep on? -- REW */
-		interruptible_sleep_on (& vcc->close_wait);
+		wait_event_interruptible(vcc->close_wait, !vcc->last_skb);
 	}
 
 	txtp = &atm_vcc->qos.txtp;