[VOL-4020]  voltha-lib-go changes for ONU SW upgrade, new Download, Activate,Retrieve APIs

Change-Id: Iaa87a1b74b5f2e25cb0ab43e47f1549683246951
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 7b1ab23..caf36a8 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -86,7 +86,7 @@
 github.com/modern-go/concurrent
 # github.com/modern-go/reflect2 v1.0.1
 github.com/modern-go/reflect2
-# github.com/opencord/voltha-protos/v4 v4.0.12
+# github.com/opencord/voltha-protos/v4 v4.1.1
 github.com/opencord/voltha-protos/v4/go/common
 github.com/opencord/voltha-protos/v4/go/ext/config
 github.com/opencord/voltha-protos/v4/go/extension