VOL-3589 Update voltha go to support new version v4 of voltha protos

Change-Id: I32074b5c05b08f8ebd2205f8dc2af225bff465cc
diff --git a/go.mod b/go.mod
index 8618262..85c3a6f 100644
--- a/go.mod
+++ b/go.mod
@@ -6,8 +6,8 @@
 	github.com/gogo/protobuf v1.3.0
 	github.com/golang/protobuf v1.3.2
 	github.com/google/uuid v1.1.1
-	github.com/opencord/voltha-lib-go/v3 v3.2.10
-	github.com/opencord/voltha-protos/v3 v3.4.2
+	github.com/opencord/voltha-lib-go/v4 v4.0.0
+	github.com/opencord/voltha-protos/v4 v4.0.2
 	github.com/phayes/freeport v0.0.0-20180830031419-95f893ade6f2
 	github.com/stretchr/testify v1.4.0
 	google.golang.org/grpc v1.24.0