[BUG] fix typo in redispatched connection

a copy-paste typo was present in the reconnection code responsible
for respatching. The client's FSM would not be re-evaluated if an
error occurred. It looks harmless but better fix it.
diff --git a/src/proto_http.c b/src/proto_http.c
index d69d8e2..30bdc39 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -2543,7 +2543,7 @@
 
 				/* first, get a connection */
 				if (srv_redispatch_connect(t))
-					return t->srv_state != SV_STIDLE;
+					return t->srv_state != SV_STCONN;
 			}
 
 			do {