Remove unused object-ref code

Signed-off-by: Martin Koegler <mkoegler@auto.tuwien.ac.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-pack-objects.c

@@ -2009,7 +2009,6 @@ static void get_object_list(int ac, const char **av)
 
 	init_revisions(&revs, NULL);
 	save_commit_buffer = 0;
-	track_object_refs = 0;
 	setup_revisions(ac, av, &revs, NULL);
 
 	while (fgets(line, sizeof(line), stdin) != NULL) {