[gdm] configure: make auto goo more gooey

[Ray Strode <halfline src gnome org>]

commit a4393cc90bdc74dcebc0d68f201ccfe6711d1f81
Author: Ray Strode <rstrode redhat com>
Date:   Mon Jul 22 16:36:09 2019 -0400

    configure: make auto goo more gooey
    
    the goo, oh, the goo.

 configure.ac | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/configure.ac b/configure.ac
index 0a1c6c19..e63cbf32 100644
--- a/configure.ac
+++ b/configure.ac
@@ -8,6 +8,7 @@ AC_CONFIG_SRCDIR([daemon/gdm-manager.c])
 
 AM_INIT_AUTOMAKE([1.11.2 no-dist-gzip dist-xz tar-ustar -Wall foreign])
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
+m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
 AM_MAINTAINER_MODE([enable])
 
 # for utmpx stuff