net: add netif_is_lag_master helper

BugLink: http://bugs.launchpad.net/bugs/1562310

Some code does not mind if the master is bond or team and treats them
the same, as generic LAG.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 7be61833)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

include/linux/netdevice.h

@@ -3899,6 +3899,11 @@ static inline bool netif_is_team_port(struct net_device *dev)
 	return dev->priv_flags & IFF_TEAM_PORT;
 }
 
+static inline bool netif_is_lag_master(struct net_device *dev)
+{
+	return netif_is_bond_master(dev) || netif_is_team_master(dev);
+}
+
 /* This device needs to keep skb dst for qdisc enqueue or ndo_start_xmit() */
 static inline void netif_keep_dst(struct net_device *dev)
 {