better wording in the tooltip

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@56861 15284696-431f-4ddb-bdfa-cd5b030d7da7

display/d.barscale/main.c

@@ -114,7 +114,7 @@ int main(int argc, char **argv)
 
     n_arrow = G_define_option();
     n_arrow->key = "north_arrow";
-    n_arrow->description = _("Only used when drawing a north arrow only");
+    n_arrow->description = _("Only used when drawing a north arrow with the -n flag");
     n_arrow->label = _("North arrow style");
     n_arrow->options = "1a,1b,2,3,4,5,6,7a,7b,8a,8b,9";
     n_arrow->answer = "1a";