[VOL-3731] Delete etcd stale data after olt reboot

Change-Id: Ib6669511327870d180262e1f8c2bd6c1e8315496
(cherry picked from commit 4f5ed59bf6dbcacbdef33ed25b4601334364275b)
diff --git a/VERSION b/VERSION
index c492825..3cf5751 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.5.6
+3.5.7