po: Don't create backup .po files

As well as preventing creation of useless backup files, it works
around a bug in gettext 0.17 on OS/X

diff --git a/po/Makevars b/po/Makevars
index 27049c1..10ed9f6 100644 (file)
--- a/po/Makevars
+++ b/po/Makevars
@@ -42,6 +42,6 @@ EXTRA_LOCALE_CATEGORIES =
 
 # Avoid line numbers in *.po, but keep them in *.pot.
 MSGMERGE = msgmerge --no-location
-MSGMERGE_UPDATE = msgmerge --no-location --update
+MSGMERGE_UPDATE = msgmerge --no-location --update --backup=off
 MSGFILTER = msgfilter --no-location