bnx2x: Allow ethtool to enable/disable loopback.

This patch updates the bnx2x_set_features() to handle loopback mode.
When enabled; it sets internal-MAC loopback.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bnx2x/bnx2x_main.c b/drivers/net/bnx2x/bnx2x_main.c
index 2762edf..f45c0ca 100644
--- a/drivers/net/bnx2x/bnx2x_main.c
+++ b/drivers/net/bnx2x/bnx2x_main.c
@@ -9273,6 +9273,9 @@
 	if (bp->flags & USING_DAC_FLAG)
 		dev->features |= NETIF_F_HIGHDMA;
 
+	/* Add Loopback capability to the device */
+	dev->hw_features |= NETIF_F_LOOPBACK;
+
 #ifdef BCM_DCBNL
 	dev->dcbnl_ops = &bnx2x_dcbnl_ops;
 #endif