VOL-2639: Creation of common errors package

Change-Id: Iac2ab83826bf072c84af81e9e2bccf61d40c07ed
diff --git a/internal/pkg/core/statsmanager.go b/internal/pkg/core/statsmanager.go
index 3133bce..0cc1b46 100755
--- a/internal/pkg/core/statsmanager.go
+++ b/internal/pkg/core/statsmanager.go
@@ -20,6 +20,7 @@
 import (
 	"fmt"
 	"github.com/opencord/voltha-lib-go/v3/pkg/log"
+	"github.com/opencord/voltha-openolt-adapter/internal/pkg/olterrors"
 	"github.com/opencord/voltha-protos/v3/go/openolt"
 	"github.com/opencord/voltha-protos/v3/go/voltha"
 	"sync"
@@ -233,7 +234,7 @@
 		return PONPorts, nil
 	} else {
 		log.Errorf("Invalid type of interface %s", Intftype)
-		return nil, NewErrInvalidValue(log.Fields{"interface-type": Intftype}, nil)
+		return nil, olterrors.NewErrInvalidValue(log.Fields{"interface-type": Intftype}, nil)
 	}
 }