md: recover_bitmaps() can be static

drivers/md/md-cluster.c:190:6: sparse: symbol 'recover_bitmaps' was not declared. Should it be static?

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 96679b2..5062bd1 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -217,7 +217,7 @@
 	return s;
 }
 
-void recover_bitmaps(struct md_thread *thread)
+static void recover_bitmaps(struct md_thread *thread)
 {
 	struct mddev *mddev = thread->mddev;
 	struct md_cluster_info *cinfo = mddev->cluster_info;