[netdrvr] kill sync_irq-before-freq_irq pattern

synchronize_irq() is superfluous when free_irq() call immediately follows it,
because free_irq() also does a synchronize_irq() call of its own.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/net/8139too.c

@@ -2231,7 +2231,6 @@ static int rtl8139_close (struct net_device *dev)
 
 	spin_unlock_irqrestore (&tp->lock, flags);
 
-	synchronize_irq (dev->irq);	/* racy, but that's ok here */
 	free_irq (dev->irq, dev);
 
 	rtl8139_tx_clear (tp);