VOL-3978 - update to go 1.16.3

Change-Id: I4a1c78722b3e4019dfd288fa9c89b7d90924050a
diff --git a/vendor/github.com/opencord/voltha-lib-go/v4/pkg/db/backend.go b/vendor/github.com/opencord/voltha-lib-go/v4/pkg/db/backend.go
index d6867a5..bf30a48 100644
--- a/vendor/github.com/opencord/voltha-lib-go/v4/pkg/db/backend.go
+++ b/vendor/github.com/opencord/voltha-lib-go/v4/pkg/db/backend.go
@@ -75,8 +75,6 @@
 
 func (b *Backend) newClient(ctx context.Context, address string, timeout time.Duration) (kvstore.Client, error) {
 	switch b.StoreType {
-	case "consul":
-		return kvstore.NewConsulClient(ctx, address, timeout)
 	case "etcd":
 		return kvstore.NewEtcdClient(ctx, address, timeout, log.WarnLevel)
 	}
@@ -170,9 +168,6 @@
 			case codes.DataLoss:
 				alive = false
 			}
-
-			//} else {
-			// TODO: Implement for consul backend; would it be needed ever?
 		}
 	}
 
@@ -239,6 +234,21 @@
 	return err
 }
 
+// DeleteWithPrefix removes items having prefix key
+func (b *Backend) DeleteWithPrefix(ctx context.Context, prefixKey string) error {
+	span, ctx := log.CreateChildSpan(ctx, "etcd-delete-with-prefix")
+	defer span.Finish()
+
+	formattedPath := b.makePath(ctx, prefixKey)
+	logger.Debugw(ctx, "deleting-prefix-key", log.Fields{"key": prefixKey, "path": formattedPath})
+
+	err := b.Client.DeleteWithPrefix(ctx, formattedPath)
+
+	b.updateLiveness(ctx, b.isErrorIndicatingAliveKvstore(ctx, err))
+
+	return err
+}
+
 // CreateWatch starts watching events for the specified key
 func (b *Backend) CreateWatch(ctx context.Context, key string, withPrefix bool) chan *kvstore.Event {
 	span, ctx := log.CreateChildSpan(ctx, "etcd-create-watch")