net: remove iflink field from struct net_device

Now that all users of iflink have the ndo_get_iflink handler available, it's
possible to remove this field.

By default, dev_get_iflink() returns the ifindex of the interface.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 788eb7a..846a1f5 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1538,7 +1538,7 @@
 	netdev_features_t	mpls_features;
 
 	int			ifindex;
-	int			iflink;
+	int			group;
 
 	struct net_device_stats	stats;
 
@@ -1741,7 +1741,6 @@
 #endif
 	struct phy_device *phydev;
 	struct lock_class_key *qdisc_tx_busylock;
-	int group;
 	struct pm_qos_request	pm_qos_req;
 };
 #define to_net_dev(d) container_of(d, struct net_device, dev)