atl1e: Fix set-but-unused variable.

The variable 'tx_ring' is set but unused in
atl1e_init_ring_resources().  Just kill it off.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/atl1e/atl1e_main.c

@@ -691,10 +691,8 @@ static void atl1e_cal_ring_size(struct atl1e_adapter *adapter, u32 *ring_size)
 
 static void atl1e_init_ring_resources(struct atl1e_adapter *adapter)
 {
-	struct atl1e_tx_ring *tx_ring = NULL;
 	struct atl1e_rx_ring *rx_ring = NULL;
 
-	tx_ring = &adapter->tx_ring;
 	rx_ring = &adapter->rx_ring;
 
 	rx_ring->real_page_size = adapter->rx_ring.page_size