add missing warning about bm_is_locked

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

drivers/block/drbd/drbd_bitmap.c

@@ -1212,6 +1212,8 @@ int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsi
 	ERR_IF(!b->bm_pages) return 1;
 
 	spin_lock_irqsave(&b->bm_lock, flags);
+	if (bm_is_locked(b))
+		bm_print_lock_info(mdev);
 	for (bitnr = s; bitnr <= e; bitnr++) {
 		w = bitnr >> LN2_BPL;
 		if (page_nr != w >> (PAGE_SHIFT - LN2_BPL + 3)) {