md: pass mddev to make_request functions rather than request_queue

We used to pass the personality make_request function direct
to the block layer so the first argument had to be a queue.
But now we have the intermediary md_make_request so it makes
at lot more sense to pass a struct mddev_s.
It makes it possible to have an mddev without its own queue too.

Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 3225e25..a536f54 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -330,7 +330,7 @@
 	int level;
 	struct list_head list;
 	struct module *owner;
-	int (*make_request)(struct request_queue *q, struct bio *bio);
+	int (*make_request)(mddev_t *mddev, struct bio *bio);
 	int (*run)(mddev_t *mddev);
 	int (*stop)(mddev_t *mddev);
 	void (*status)(struct seq_file *seq, mddev_t *mddev);