#56 tripwire-2.4.2.2 builds fails with automake-1.13

When using automake-1.13 tripwire-2.4.2.2 build fails with error:

configure.in:9: error: 'AM_CONFIG_HEADER': this macro is obsolete.
You should use the 'AC_CONFIG_HEADERS' macro instead.
/usr/share/aclocal-1.13/obsolete-err.m4:12: AM_CONFIG_HEADER is expanded from...
configure.in:9: the top level

Attached patch to fix configure.in

More info at:

https://bugs.gentoo.org/show_bug.cgi?id=467542