- Refactor listening socket list. All of the listening sockets are

now maintained in a single linked-list in a transport-independent manner.
- Use queue.h for linked-list structure.
- Use linked-list for AllowedPeers.
- Use getaddrinfo(8) even for Unix Domain sockets.
- Use macros to type-casting from/to struct sockaddr{,_in,_in6}.
- Define fu_* macro for union f_un to shorten the member names.
- Remove an extra #include <sys/type.h>.
- Add "static" to non-exported symbols.
- !INET support is still incomplete but will be fixed later.

There is no functional change except for some minor debug messages.

usr.sbin/syslogd/Makefile

@@ -13,6 +13,9 @@ LIBADD=	util
 
 WARNS?= 3
 
+.if ${MK_INET_SUPPORT} != "no"
+CFLAGS+= -DINET
+.endif
 .if ${MK_INET6_SUPPORT} != "no"
 CFLAGS+= -DINET6
 .endif