net/mlx4_en: Set number of rx/tx channels using ethtool

Add support to changing number of rx/tx channels using
ethtool ('ethtool -[lL]'). Where the number of tx channels specified in ethtool
is the number of rings per user priority - not total number of tx rings.

Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index b35094c..1f571d0 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -523,7 +523,7 @@
 u16 mlx4_en_select_queue(struct net_device *dev, struct sk_buff *skb)
 {
 	struct mlx4_en_priv *priv = netdev_priv(dev);
-	u16 rings_p_up = priv->mdev->profile.num_tx_rings_p_up;
+	u16 rings_p_up = priv->num_tx_rings_p_up;
 	u8 up = 0;
 
 	if (dev->num_tc)