Add CONFIGDIR to the fallback config where can be specified by --with-configdir
diff --git a/src/fcinit.c b/src/fcinit.c
index 0e1421e..99df9b4 100644
--- a/src/fcinit.c
+++ b/src/fcinit.c
@@ -45,6 +45,7 @@
 	"  <dir prefix=\"xdg\">fonts</dir>" \
 	"  <cachedir>" FC_CACHEDIR "</cachedir>" \
 	"  <cachedir prefix=\"xdg\">fontconfig</cachedir>" \
+	"  <include ignore_missing=\"yes\">" CONFIGDIR "</include>" \
 	"  <include ignore_missing=\"yes\" prefix=\"xdg\">fontconfig/conf.d</include>" \
 	"  <include ignore_missing=\"yes\" prefix=\"xdg\">fontconfig/fonts.conf</include>" \
 	"</fontconfig>";