ares: return error at once if timed out before name resolve starts

Pointed-out-by: Ray Satiro
Bug: https://curl.haxx.se/mail/lib-2017-03/0004.html
diff --git a/lib/asyn-ares.c b/lib/asyn-ares.c
index c038c2a..ae73d05 100644
--- a/lib/asyn-ares.c
+++ b/lib/asyn-ares.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -359,6 +359,11 @@
   struct Curl_dns_entry *temp_entry;
 
   timeout = Curl_timeleft(data, &now, TRUE);
+  if(timeout < 0) {
+    /* already expired! */
+    connclose(conn, "Timed out before name resolve started");
+    return CURLE_OPERATION_TIMEDOUT;
+  }
   if(!timeout)
     timeout = CURL_TIMEOUT_RESOLVE * 1000; /* default name resolve timeout */