[gdm] configure: bump to 3.21.4

[Ray Strode <halfline src gnome org>]

commit 739d06359fe9a46527126202c501e4a3dc708892
Author: Ray Strode <rstrode redhat com>
Date:   Fri Jul 22 13:36:15 2016 -0400

    configure: bump to 3.21.4

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 9ffa7d1..8f3a870 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,7 +1,7 @@
 
 AC_PREREQ([2.60])
 AC_INIT([gdm],
-        [3.21.3],
+        [3.21.4],
         [http://bugzilla.gnome.org/enter_bug.cgi?product=gdm])
 
 AC_CONFIG_SRCDIR([daemon/gdm-manager.c])