Moving all references to proto v4

Change-Id: Idbb9119da7ddae136f7ffbbb783429c7e049b3ab
diff --git a/protos/voltha_protos/openolt.proto b/protos/voltha_protos/openolt.proto
index b647b4a..dc9946f 100644
--- a/protos/voltha_protos/openolt.proto
+++ b/protos/voltha_protos/openolt.proto
@@ -14,7 +14,7 @@
 
 syntax = "proto3";
 
-option go_package = "github.com/opencord/voltha-protos/v3/go/openolt";
+option go_package = "github.com/opencord/voltha-protos/v4/go/openolt";
 option java_package = "org.opencord.voltha.openolt";
 option java_outer_classname = "VolthaOpenOLT";