[mutter] cogl: Export two more functions

[Jonas Ådahl <jadahl src gnome org>]

commit 8748841094b6bf1acf923201392156b03191c409
Author: Florian Müllner <fmuellner gnome org>
Date:   Sat Mar 28 23:01:10 2020 +0100

    cogl: Export two more functions
    
    cogl_object_[get|set]_value_object() are annotated as [get|set]-value-func
    for objects and primitives, so they must be visible for any derived types
    to be usable from introspection.
    
    https://gitlab.gnome.org/GNOME/mutter/-/issues/1146

 cogl/cogl/cogl-gtype-private.h | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/cogl/cogl/cogl-gtype-private.h b/cogl/cogl/cogl-gtype-private.h
index e7505264f..7ba270651 100644
--- a/cogl/cogl/cogl-gtype-private.h
+++ b/cogl/cogl/cogl-gtype-private.h
@@ -269,8 +269,10 @@ void _cogl_gtype_object_class_base_finalize (CoglObjectClass *klass);
 void _cogl_gtype_object_class_init (CoglObjectClass *klass);
 void _cogl_gtype_object_init (CoglObject *object);
 
+COGL_EXPORT
 void cogl_object_value_set_object (GValue   *value,
                                    gpointer  object);
+COGL_EXPORT
 gpointer cogl_object_value_get_object (const GValue *value);
 
 void _cogl_gtype_dummy_iface_init (gpointer iface);