[seahorse] Fix build with automake 1.13

[Stefan Walter <stefw src gnome org>]

commit d4e4113b3bc37165de6b39ff47b0677962319094
Author: Nuno Araujo <nuno araujo russo79 com>
Date:   Tue Jan 29 08:55:53 2013 +0100

    Fix build with automake 1.13
    
    In Automake 1.13, the long-deprecated macro AM_CONFIG_HEADER (deprecated since
    2002) has been removed in favour of AC_CONFIG_HEADERS.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=692770

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index a63c01e..7f799f9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,7 +16,7 @@ AVAHI_GLIB_REQUIRED=0.6
 
 AM_INIT_AUTOMAKE([1.11 tar-ustar foreign -Wno-portability])
 AM_SANITY_CHECK
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS([config.h])
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 AM_MAINTAINER_MODE([enable])
 AC_CONFIG_MACRO_DIR([m4])