Use make functions for HELP_LINGUAS

Author: rbuj

help/Makefile.am

@@ -6,10 +6,10 @@ HELP_MEDIA = figures/mate-terminal-default.png \
              figures/mate-terminal-tabbed.png 
 #	      figures/terminal-window.png   This image is not used.
 
-HELP_LINGUAS = da de ca cs el en_GB es fr it ko oc pt_BR ru sv uk zh_CN
-
-
-# Move to HELP_LINGUAS in transition to yelp-tools
-#SUBDIRS = bg ro ja zh_TW
+# Add linguas to be ignored, e.g. IGNORE_HELP_LINGUAS = ca de es fr
+IGNORE_HELP_LINGUAS =
+HELP_LINGUAS = $(if $(IGNORE_HELP_LINGUAS), \
+	$(filter-out $(IGNORE_HELP_LINGUAS),$(subst /,,$(dir $(wildcard */*.po)))), \
+	$(subst /,,$(dir $(wildcard */*.po))) )
 
 -include $(top_srcdir)/git.mk