Fix fetch/clone --quiet when stdout is connected

Fixes the `git clone --quiet` issue raised by Dave Jones in
http://marc.info/?l=git&m=121529226023180&w=2

With this simple patch applied we no longer see the following remote
messages as no-progress is correctly sent to the remote site:

  remote: Counting objects: 84102, done.
  remote: Compressing objects: 100% (24720/24720), done.
  remote: Total 84102 (delta 60949), reused 80810 (delta 57900)
Signed-off-by: NTuncer Ayaz <tuncer.ayaz@gmail.com>
Acked-by: NDaniel Barkalow <barkalow@iabervon.org>
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>

transport.c

@@ -643,8 +643,8 @@ static int fetch_refs_via_pack(struct transport *transport,
 	args.use_thin_pack = data->thin;
 	args.include_tag = data->followtags;
 	args.verbose = (transport->verbose > 0);
-	args.quiet = args.no_progress = (transport->verbose < 0);
-	args.no_progress = !isatty(1);
+	args.quiet = (transport->verbose < 0);
+	args.no_progress = args.quiet || !isatty(1);
 	args.depth = data->depth;
 
 	for (i = 0; i < nr_heads; i++)