configure: replace deprecated AM_CONFIG_HEADER with AC_CONFIG_HEADERS

AM_CONFIG_HEADER has been removed in the just-released automake 1.13:
https://lists.gnu.org/archive/html/automake/2012-12/msg00038.html

https://bugzilla.gnome.org/show_bug.cgi?id=690881

diff --git a/configure.ac b/configure.ac
index 1245546..37e67fc 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -22,7 +22,7 @@ dnl can autoconf find the source ?
 AC_CONFIG_SRCDIR([ext/mad/gstmad.c])
 
 dnl define the output header for config
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS(config.h)
 
 dnl AM_MAINTAINER_MODE only provides the option to configure to enable it
 AM_MAINTAINER_MODE([enable])