use autoreconf instead of calling separate tools

this has been the correct way since a long time.

Pointed-out-by: Felipe Contreras <felipe.contreras@gmail.com>

autogen.sh

@@ -1,7 +1,4 @@
 #! /bin/sh
 set -e -v
 make -f Makefile.am log
-aclocal
-autoheader
-automake --add-missing
-autoconf
+autoreconf -f -i