libaosd: mark broken on darwin

While this can be made to compile on darwin:
- override cairo with x11Support
- fixup dylib paths in the binary
- add explicit libXrender for darwin

the app crashes anyway on floating point exception and doesn't do anything.

pkgs/development/libraries/libaosd/default.nix

···
       composited rendering via XComposite, as well as support for
       rendering Cairo and Pango layouts.
     '';
+    broken = stdenv.isDarwin;
     homepage = "https://github.com/atheme-legacy/libaosd";
     license = licenses.mit;
     maintainers = with maintainers; [ unode ];