mlx4_en: multiqueue support

By default the driver opens 8 TX queues (defined by MLX4_EN_NUM_TX_RINGS).
If the driver is configured to support Per Priority Flow Control, we open
8 additional TX rings.
dev->real_num_tx_queues is always set to be MLX4_EN_NUM_TX_RINGS.
The mlx4_en_select_queue() function uses standard hashing (skb_tx_hash)
in case that PPFC is not supported or the skb contain a vlan tag,
otherwise the queue is selected according to vlan priority.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/mlx4/en_main.c b/drivers/net/mlx4/en_main.c
index b510000..9ed4a15 100644
--- a/drivers/net/mlx4/en_main.c
+++ b/drivers/net/mlx4/en_main.c
@@ -93,13 +93,8 @@
 		params->prof[i].tx_ppp = pfctx;
 		params->prof[i].tx_ring_size = MLX4_EN_DEF_TX_RING_SIZE;
 		params->prof[i].rx_ring_size = MLX4_EN_DEF_RX_RING_SIZE;
-	}
-	if (pfcrx || pfctx) {
-		params->prof[1].tx_ring_num = MLX4_EN_TX_RING_NUM;
-		params->prof[2].tx_ring_num = MLX4_EN_TX_RING_NUM;
-	} else {
-		params->prof[1].tx_ring_num = 1;
-		params->prof[2].tx_ring_num = 1;
+		params->prof[i].tx_ring_num = MLX4_EN_NUM_TX_RINGS +
+			(!!pfcrx) * MLX4_EN_NUM_PPP_RINGS;
 	}
 
 	return 0;