iptables 1.8.7 release
configure: bump version for 1.8.7 release

Update libtool version for libxtables since two new interfaces have been
added:

- xtables_parse_mac_and_mask()
- xtables_print_well_known_mac_and_mask()

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1 file changed