libxtables: xtables_ipmask_to_numeric incorrect with non-CIDR masks

As pointed out by Peter Hoelsken, rules created with non-standard
masks such as 0.255.0.0, 0.0.255.0, etc. are displayed when output
with iptables -L in CIDR notation as -1.  This is because the cidr
variable in xtables_ipmask_to_numeric is unsigned, and the return
value of -1 from xtables_ipmask_to_cidr is therefore converted to
UINT_MAX. Add a cast to workaround the issue.

This closes netfilter bugzilla #854.

Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
extensions: libxt_LOG: use generic syslog reference in manpage

Fedora, ArchLinux, Ubuntu, and Debian, at the least, use
alternative syslog daemons by default these days. Let's make
the syslog reference generic.

Reference: http://bugs.debian.org/567564

Signed-off-by: Laurence J. Lane <ljlane@debian.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
iptables: extensions/GNUMakefile.in use CPPFLAGS

"All other Makefiles add CPPFLAGS to ${COMPILE} (automake), but GNUmakefile.in
 doesn't set it."

http://bugs.debian.org/665286

Signed-off-by: Laurence J. Lane <ljlane@debian.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>