[gegl] workshop: add a missing const Babl

[Mikael Magnusson <mikachu src gnome org>]

commit 76a5f936a24f12cc283b85e975d7e24efafbae3f
Author: Mikael Magnusson <mikachu src gnome org>
Date:   Fri Mar 23 13:24:12 2012 +0100

    workshop: add a missing const Babl

 operations/workshop/external/gluas.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/operations/workshop/external/gluas.c b/operations/workshop/external/gluas.c
index 536f1d9..43754b7 100644
--- a/operations/workshop/external/gluas.c
+++ b/operations/workshop/external/gluas.c
@@ -60,7 +60,7 @@ typedef struct Priv
   GeglBuffer *in_drawable;
   GeglBuffer *aux_drawable;
   GeglBuffer *out_drawable;
-  Babl       *rgba_float;
+  const Babl *rgba_float;
 
   gint        bx1, by1;
   gint        bx2, by2;    /* mask bounds */