[babl] force generate git-version.h before copying

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

commit 0bada2f8150ade88945fd5fbb126442bee064cff
Author: Félix Piédallu <felix piedallu me>
Date:   Wed Jul 24 13:35:26 2019 +0200

    force generate git-version.h before copying

 babl/meson.build | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/babl/meson.build b/babl/meson.build
index b2a2d4e..2a27063 100644
--- a/babl/meson.build
+++ b/babl/meson.build
@@ -56,6 +56,9 @@ if is_git_repo
     command: [ git_bin.path(), 'describe', '--always' ],
   )
 
+  meson.add_dist_script(
+    [ 'ninja', git_version_h.full_path(), ],
+  )
   meson.add_dist_script(
     [ 'sh', '-c', ' '.join(
     [ 'cp', git_version_h.full_path(), '${MESON_DIST_ROOT}/babl' ]