tipc: Eliminate obsolete code for re-sending a message

Removes code that updated the "previous node" field of an out-going
message over TIPC's links. Such updating is unnecessary since the
removal of the prototype multi-cluster capability means that all
outgoing messages are generated locally and already have this field
populated correctly.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

net/tipc/link.c

@@ -871,8 +871,6 @@ int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
 	u32 queue_limit = l_ptr->queue_limit[imp];
 	u32 max_packet = l_ptr->max_pkt;
 
-	msg_set_prevnode(msg, tipc_own_addr);	/* If routed message */
-
 	/* Match msg importance against queue limits: */
 
 	if (unlikely(queue_size >= queue_limit)) {