configure: add --without-ipulog option to disable libipulog build

This is a compat library used for netfilter ULOG target.
ULOG only works with IPv4. NFLOG has replaced ULOG.

Signed-off-by: Matthieu Crapet <Matthieu.Crapet@ingenico.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>