xfce4-settings: update to 4.16.3

This release contains a single significant bug fix which ensures it
works with libX11 >= 1.8 (and pkgsrc and NetBSD -current were both just
updated to 1.8.1).

4.16.3
======
- xfsettingsd: Fix recursive lock in libX11 (Fixes #369)
- build: Fix intltool lock file problem during make distcheck
- Translation Updates:
  Armenian (Armenia), Belarusian, Catalan, English (Canada), English
  (United Kingdom), Estonian, Galician, Greek, Indonesian, Kazakh,
  Korean, Lithuanian, Malay, Occitan (post 1500), Polish, Romanian,
  Swedish

(gutteridge)