[planner] Update POTFILES.skip

[Piotr Drąg <piotrdrag src gnome org>]

commit 9a7df13926e02dcd8571e3e5036e4a92de1ef99c
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Sun May 7 13:21:14 2017 +0200

    Update POTFILES.skip

 po/POTFILES.skip |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/po/POTFILES.skip b/po/POTFILES.skip
index 694848a..d65c217 100644
--- a/po/POTFILES.skip
+++ b/po/POTFILES.skip
@@ -8,3 +8,5 @@ data/planner.desktop.in
 
 eds-backend/e-cal-backend-planner.c
 eds-backend/planner-source/planner-source.c
+
+sub/data/planner.desktop.in