gfio: start of per-job option edit

Currently we don't properly handle job files with multiple
job entries in them, each one just overwrites the last.
Start tracking all of them.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/gfio.h b/gfio.h
index b8de680..854f7ad 100644
--- a/gfio.h
+++ b/gfio.h
@@ -136,11 +136,16 @@
 	struct thread_stat ts;
 };
 
+struct gfio_client_options {
+	struct flist_head list;
+	struct thread_options o;
+};
+
 struct gfio_client {
 	struct gui_entry *ge;
 	struct fio_client *client;
 	GtkWidget *err_entry;
-	struct thread_options o;
+	struct flist_head o_list;
 
 	struct end_results *results;
 	unsigned int nr_results;