sctp: Make the ctl_sock per network namespace

- Kill sctp_get_ctl_sock, it is useless now.
- Pass struct net where needed so net->sctp.ctl_sock is accessible.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sctp/sctp.h

@@ -114,7 +114,6 @@
 /*
  * sctp/protocol.c
  */
-extern struct sock *sctp_get_ctl_sock(void);
 extern int sctp_copy_local_addr_list(struct net *, struct sctp_bind_addr *,
 				     sctp_scope_t, gfp_t gfp,
 				     int flags);