Use voltha-protos version 4.0.2
Bump major version of voltha-lib-go to 4.0.0 as this change results
in incompatible API version compared to previous version

Change-Id: I1def58361fb1d85f07d6948ebf1ffb7a92eb0d4c
diff --git a/VERSION b/VERSION
index 15a2799..fcdb2e1 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.3.0
+4.0.0