Untangle the file creation mess

Still needs a lot of work, will do a rewrite of this soonish. At
least it should work now.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fio.c b/fio.c
index de5c976..a416856 100644
--- a/fio.c
+++ b/fio.c
@@ -773,6 +773,9 @@
 	if (open_files(td))
 		goto err;
 
+	if (init_random_map(td))
+		goto err;
+
 	if (td->o.exec_prerun) {
 		if (system(td->o.exec_prerun) < 0)
 			goto err;