l2tp: remove .show from struct l2tp_tunnel

This callback has never been implemented.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/l2tp/l2tp_core.h

@@ -180,9 +180,6 @@ struct l2tp_tunnel {
 	struct net		*l2tp_net;	/* the net we belong to */
 
 	refcount_t		ref_count;
-#ifdef CONFIG_DEBUG_FS
-	void (*show)(struct seq_file *m, void *arg);
-#endif
 	int (*recv_payload_hook)(struct sk_buff *skb);
 	void (*old_sk_destruct)(struct sock *);
 	struct sock		*sock;		/* Parent socket */

net/l2tp/l2tp_debugfs.c

@@ -177,9 +177,6 @@ static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
 		   atomic_long_read(&tunnel->stats.rx_packets),
 		   atomic_long_read(&tunnel->stats.rx_bytes),
 		   atomic_long_read(&tunnel->stats.rx_errors));
-
-	if (tunnel->show != NULL)
-		tunnel->show(m, tunnel);
 }
 
 static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)