Bump BBSIM chart for voltha-2.4

Change-Id: I14df739a5cf0fc9ed8f4a5925e6b927c7a455616
diff --git a/VERSION b/VERSION
index 831446c..ac14c3d 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-5.1.0
+5.1.1