[gimp] app: don't sanity check for "gegl:matting-levin".

[Jehan <jehanp src gnome org>]

commit 97247f41ea51642609de5efab3cc0a82727c4087
Author: Jehan <jehan girinstud io>
Date:   Mon Sep 17 17:01:29 2018 +0200

    app: don't sanity check for "gegl:matting-levin".
    
    My previous commit answers the forever question "do we want to require
    this?" which was in comments and can now be removed.
    We don't need to actually require this operation for running GIMP, as it
    runs fine without. Just testing in configure is enough of a warning for
    the missing feature.

 app/sanity.c | 1 -
 1 file changed, 1 deletion(-)
---
diff --git a/app/sanity.c b/app/sanity.c
index 17cf58d514..7586beac53 100644
--- a/app/sanity.c
+++ b/app/sanity.c
@@ -657,7 +657,6 @@ sanity_check_gegl_ops (void)
     "gegl:map-absolute",
     "gegl:map-relative",
     "gegl:matting-global",
-/*  "gegl:matting-levin",*/ /* XXX: do we want to require this? */
     "gegl:maze",
     "gegl:median-blur",
     "gegl:mirrors",