[gegl] buffer: mark old gegl_buffer_iterator_new function as deprecated

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

commit 6475cc8d480b3d9c3696ac82badedf9ca0551b1a
Author: Øyvind Kolås <pippin gimp org>
Date:   Mon Sep 10 23:36:13 2018 +0200

    buffer: mark old gegl_buffer_iterator_new function as deprecated
    
    The way to get rid of deprecation warnings is to, at the top of the file before
    gegl-buffer-iterator2.h the 2 suffix is not to be used, effectively this means
    that the constructor now takes an additional argument which is the maximum
    number of buffers the iterator should be allocated to support, and access to
    roi/data members need to be adjusted to be fields of the new array items.
    
    When we've gotten rid of all warnings in GIMP the following release of GEGL,
    gegl-buffer-iterator2.h will be copied over gegl-buffer-iterator.h and the
    macro will no longer add the 2 suffix.

 gegl/buffer/gegl-buffer-iterator.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gegl/buffer/gegl-buffer-iterator.h b/gegl/buffer/gegl-buffer-iterator.h
index 8ff6f984e..a55f4ea3a 100644
--- a/gegl/buffer/gegl-buffer-iterator.h
+++ b/gegl/buffer/gegl-buffer-iterator.h
@@ -80,7 +80,7 @@ GeglBufferIterator * gegl_buffer_iterator_new  (GeglBuffer          *buffer,
                                                 gint                 level,
                                                 const Babl          *format,
                                                 GeglAccessMode       access_mode,
-                                                GeglAbyssPolicy      abyss_policy);
+                                                GeglAbyssPolicy      abyss_policy) G_DEPRECATED;
 
 
 /**