[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/drivers/net/hamradio/hdlcdrv.c b/drivers/net/hamradio/hdlcdrv.c
index b33adc6..ae9629f 100644
--- a/drivers/net/hamradio/hdlcdrv.c
+++ b/drivers/net/hamradio/hdlcdrv.c
@@ -682,8 +682,7 @@
 
 	s->skb = NULL;
 	
-	dev->hard_header = ax25_hard_header;
-	dev->rebuild_header = ax25_rebuild_header;
+	dev->header_ops = &ax25_header_ops;
 	dev->set_mac_address = hdlcdrv_set_mac_address;
 	
 	dev->type = ARPHRD_AX25;           /* AF_AX25 device */