Log Message:
Teach security/tcp_wrappers to build on NetBSD systems.  Remove the
ONLY_FOR_PLATFORMS setting and simply allow the build to fail on systems
on which it currently doesn't build.  Replace the cascading if statement
that set the Makefile target with something more compact.  Lastly, teach
tcp_wrappers to partially honor PKG_SYSCONFDIR -- it will default to the
historic locations /etc/host.{allow,deny} for the config files, but if
PKG_SYSCONFDIR.tcp_wrappers is set in /etc/mk.conf, then it will use that
instead.