effectv: Chain up finalize to the parent class in warptv

Fixes a memory leak.
diff --git a/gst/effectv/gstwarp.c b/gst/effectv/gstwarp.c
index 80c6b82..dae2604 100644
--- a/gst/effectv/gstwarp.c
+++ b/gst/effectv/gstwarp.c
@@ -244,6 +244,8 @@
   warptv->offstable = NULL;
   g_free (warptv->disttable);
   warptv->disttable = NULL;
+
+  G_OBJECT_CLASS (parent_class)->finalize (object);
 }
 
 static void