Fix crash when using --inetd.

Change "local" argument to socket_do_listen() to avoid calling
"local->ai_addr" in the caller for the "do_listen == FALSE" case,
in which case it could be NULL.

Also, ensure "ai" is always initialized in socket_listen_accept() for
the "!remote_dynamic" case - otherwise it will sometimes(!) crash in
addrlist_match() later on.

Get rid of spurious operator precedence warning concerning
GETADDR_CACHE_MASK.

Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-by: Arne Schwabe <arne@rfc2549.org>
Message-Id: <1396181376-32022-1-git-send-email-gert@greenie.muc.de>
URL: http://article.gmane.org/gmane.network.openvpn.devel/8412