Fix: [Network] also count the person downloading the map in the queue

Strictly seen, there are "N" people -waiting- in front of you
in the queue, but it is nicer to show "N + 1" for the person that
is currently downloading the map. Avoids it showing:
"0 clients in front of you". That just feels a bit off.

(cherry picked from commit 3677418225)

src/network/network_server.cpp

@@ -575,7 +575,7 @@ NetworkRecvStatus ServerNetworkGameSocketHandler::SendWelcome()
 /** Tell the client that its put in a waiting queue. */
 NetworkRecvStatus ServerNetworkGameSocketHandler::SendWait()
 {
-	int waiting = 0;
+	int waiting = 1; // current player getting the map counts as 1
 	Packet *p;
 
 	/* Count how many clients are waiting in the queue, in front of you! */