[MEDIUM] process_srv: don't rely at all on client state

A new buffer flag BF_MAY_CONNECT has been added so that the server
FSM can check whether it is allowed to establish a connection or
not. That way, the client FSM only has to move this flag and the
server side does not need to monitor client state anymore.
diff --git a/src/client.c b/src/client.c
index a4d5265..e04a066 100644
--- a/src/client.c
+++ b/src/client.c
@@ -341,6 +341,9 @@
 		if (p->mode == PR_MODE_HTTP) /* reserve some space for header rewriting */
 			s->req->rlim -= MAXREWRITE;
 
+		if (s->cli_state == CL_STDATA)
+			s->req->flags |= BF_MAY_CONNECT;  /* don't wait to establish connection */
+
 		s->req->rto = s->fe->timeout.client;
 		s->req->wto = s->be->timeout.server;
 		s->req->cto = s->be->timeout.connect;