[NET]: Move hardware header operations out of netdevice.

Since hardware header operations are part of the protocol class
not the device instance, make them into a separate object and
save memory.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/8021q/vlan.h b/net/8021q/vlan.h
index 7df5b29..cf4a80d 100644
--- a/net/8021q/vlan.h
+++ b/net/8021q/vlan.h
@@ -53,8 +53,8 @@
 int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
 		  struct packet_type *ptype, struct net_device *orig_dev);
 int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
-			 unsigned short type, void *daddr, void *saddr,
-			 unsigned len);
+			 unsigned short type, const void *daddr,
+			 const void *saddr, unsigned len);
 int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev);
 int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb, struct net_device *dev);
 int vlan_dev_change_mtu(struct net_device *dev, int new_mtu);