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/pkg/ponresourcemanager/ponresourcemanager.go b/pkg/ponresourcemanager/ponresourcemanager.go
index baff575..bbfebe3 100755
--- a/pkg/ponresourcemanager/ponresourcemanager.go
+++ b/pkg/ponresourcemanager/ponresourcemanager.go
@@ -25,10 +25,10 @@
 	"time"
 
 	bitmap "github.com/boljen/go-bitmap"
-	"github.com/opencord/voltha-lib-go/v3/pkg/db"
-	"github.com/opencord/voltha-lib-go/v3/pkg/db/kvstore"
-	"github.com/opencord/voltha-lib-go/v3/pkg/log"
-	tp "github.com/opencord/voltha-lib-go/v3/pkg/techprofile"
+	"github.com/opencord/voltha-lib-go/v4/pkg/db"
+	"github.com/opencord/voltha-lib-go/v4/pkg/db/kvstore"
+	"github.com/opencord/voltha-lib-go/v4/pkg/log"
+	tp "github.com/opencord/voltha-lib-go/v4/pkg/techprofile"
 )
 
 const (