VOL-2189 update voltha-openolt-adapter to use voltha-protos=v2.0.1 and voltha-lib-go=v2.2.9;
Release v2.2.1

Change-Id: I527d6541f9d8b7df8504d886a01163c7e57bdd77
diff --git a/VERSION b/VERSION
index 84e6d84..c043eea 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.2.1-dev
+2.2.1