[babl] meson: fix export_packages for generate_gir

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

commit 1cd557ce6873b08e66e0434a5ff8b2a2faa97f7b
Author: Lukas Oberhuber <lukaso gmail com>
Date:   Tue Jul 5 15:07:34 2022 +0000

    meson: fix export_packages for generate_gir
    
    This is required in order for babl to link properly in vapigen.
    
    C.f. 
https://gitlab.gnome.org/Infrastructure/gimp-macos-build/-/commit/22fc8dafa3e5edc065c035b12024bb7ebb35801a
    last file

 babl/meson.build | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/babl/meson.build b/babl/meson.build
index 70fb13144..6e7c57f44 100644
--- a/babl/meson.build
+++ b/babl/meson.build
@@ -156,6 +156,7 @@ if build_gir
     namespace: 'Babl',
     nsversion: api_version,
     header: 'babl.h',
+    export_packages: 'babl-0.1',
     install: true,
   )