[babl] babl.h: reorder BablModelFlag typedef and enum for C++ compatibility

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

commit b52d05bc25d5bda38da544129ae21905bacb52aa
Author: Øyvind Kolås <pippin gimp org>
Date:   Tue Nov 27 00:42:45 2018 +0100

    babl.h: reorder BablModelFlag typedef and enum for C++ compatibility

 babl/babl.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/babl/babl.h b/babl/babl.h
index 93cb615..43d1a35 100644
--- a/babl/babl.h
+++ b/babl/babl.h
@@ -285,7 +285,6 @@ const Babl * babl_format_get_model             (const Babl *format);
 
 
 
-typedef enum _BablModelFlag BablModelFlag;
 
 enum _BablModelFlag
 {
@@ -303,6 +302,8 @@ enum _BablModelFlag
   BABL_MODEL_FLAG_PERCEPTUAL    = 1<<10,
 };
 
+typedef enum _BablModelFlag BablModelFlag;
+
 /* linear, nonlinear and perceptual could occupy two bits with a decidated 0,
  * but we do not have a lack of bits in this bit pattern so leave it be.
  */