vlan: don't call ndo_vlan_rx_register on hardware that doesn't have vlan support

This patch removes the call to ndo_vlan_rx_register if the underlying
device doesn't have hardware support for VLAN.
Signed-off-by: Antoine Reversat <a.reversat@gmail.com>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>

net/8021q/vlan.c

@@ -205,7 +205,7 @@ int register_vlan_dev(struct net_device *dev)
 	grp->nr_vlans++;
 
 	if (ngrp) {
-		if (ops->ndo_vlan_rx_register)
+		if (ops->ndo_vlan_rx_register && (real_dev->features & NETIF_F_HW_VLAN_RX))
 			ops->ndo_vlan_rx_register(real_dev, ngrp);
 		rcu_assign_pointer(real_dev->vlgrp, ngrp);
 	}