tests/acceptance: Add test that runs NetBSD 4.0 installer on PRep/40p

tests/acceptance: Add test that runs NetBSD 4.0 installer on PRep/40p

As of this commit, NetBSD 4.0 is very old. However it is enough to
test the PRep/40p machine.

User case from:
http://mail-index.netbsd.org/port-prep/2017/04/11/msg000112.html

Reviewed-by: Hervé Poussineau <hpoussin@reactos.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20191028073441.6448-14-philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
[Cleber: fixed file name and imports]
Signed-off-by: Cleber Rosa <crosa@redhat.com>