tipc: same receive code path for connection protocol and data messages

As a preparation to eliminate port_lock we need to bring reception
of connection protocol messages under proper protection of bh_lock_sock
or socket owner.

We fix this by letting those messages follow the same code path as
incoming data messages.

As a side effect of this change, the last reference to the function
net_route_msg() disappears, and we can eliminate that function.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index bfe79bb..d838a4b 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1416,6 +1416,11 @@
 	unsigned int limit = rcvbuf_limit(sk, buf);
 	int rc = TIPC_OK;
 
+	if (unlikely(msg_user(msg) == CONN_MANAGER)) {
+		tipc_port_proto_rcv(&tsk->port, buf);
+		return TIPC_OK;
+	}
+
 	/* Reject message if it is wrong sort of message for socket */
 	if (msg_type(msg) > TIPC_DIRECT_MSG)
 		return -TIPC_ERR_NO_PORT;