[planner] Fix autotools obsolete macro which breaks the build.

[Luis Menina <lmenina src gnome org>]

commit ae25a041591c005dcf70b2b391620db9bf28f509
Author: Luis Menina <liberforce freeside fr>
Date:   Sat Jul 27 10:00:36 2013 +0200

    Fix autotools obsolete macro which breaks the build.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 77127c3..a3610b3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -5,7 +5,7 @@ AC_PREREQ(2.54)
 AC_INIT(AUTHORS)
 AM_INIT_AUTOMAKE(planner, 0.14.6)
 m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS(config.h)
 
 AC_ISC_POSIX
 AC_PROG_CC