et131x: Fix logical vs bitwise check in et131x_tx_timeout()

We should be using a logical check here instead of a bitwise operation
to check if the device is closed already in et131x_tx_timeout().

Reported-by: coverity (CID 146498)
Fixes: 38df6492 ("et131x: Add PCIe gigabit ethernet driver et131x to drivers/net")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/agere/et131x.c

@@ -3851,7 +3851,7 @@ static void et131x_tx_timeout(struct net_device *netdev)
 	unsigned long flags;
 
 	/* If the device is closed, ignore the timeout */
-	if (~(adapter->flags & FMP_ADAPTER_INTERRUPT_IN_USE))
+	if (!(adapter->flags & FMP_ADAPTER_INTERRUPT_IN_USE))
 		return;
 
 	/* Any nonrecoverable hardware error?