[gegl] jp2-load: remove unnedd cast in g_clear_pointer

[Øyvind "pippin" Kolås <ok src gnome org>]

commit ed3cc6124cb7832eecaf4e3ff22d158fddf75e19
Author: Øyvind Kolås <pippin gimp org>
Date:   Mon Oct 22 17:18:48 2018 +0200

    jp2-load: remove unnedd cast in g_clear_pointer

 operations/external/jp2-load.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/operations/external/jp2-load.c b/operations/external/jp2-load.c
index c96917cbf..2d836265a 100644
--- a/operations/external/jp2-load.c
+++ b/operations/external/jp2-load.c
@@ -57,7 +57,7 @@ cleanup(GeglOperation *operation)
 
   if (p != NULL)
     {
-      g_clear_pointer (&p->image, (GDestroyNotify) jas_image_destroy);
+      g_clear_pointer (&p->image, jas_image_destroy);
       g_clear_object (&p->file);
 
       p->width = p->height = 0;