Phonet: sockets list through proc_fs

This provides a list of sockets with their Phonet bind addresses and
some socket debug informations through /proc/net/phonet.

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/phonet/pn_dev.h b/include/net/phonet/pn_dev.h
index 29d1267..44c923c 100644
--- a/include/net/phonet/pn_dev.h
+++ b/include/net/phonet/pn_dev.h
@@ -49,4 +49,6 @@
 
 #define PN_NO_ADDR	0xff
 
+extern const struct file_operations pn_sock_seq_fops;
+
 #endif