[pygobject] meson: remove subprojects we don't use

[Christoph Reiter <creiter src gnome org>]

commit 85b199116813a33a1d9aeae1b89f80938d80d36c
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Sun May 6 21:23:02 2018 +0200

    meson: remove subprojects we don't use

 subprojects/.gitignore         | 2 --
 subprojects/proxy-libintl.wrap | 4 ----
 subprojects/zlib.wrap          | 4 ----
 3 files changed, 10 deletions(-)
---
diff --git a/subprojects/.gitignore b/subprojects/.gitignore
index 9c1d4526..2198ec12 100644
--- a/subprojects/.gitignore
+++ b/subprojects/.gitignore
@@ -1,5 +1,3 @@
 glib
 libffi
-proxy-libintl
-zlib
 gobject-introspection