We don't use anything from <sys/socket.h> (we need to know the AF_

We don't use anything from <sys/socket.h> (we need to know the AF_
values of the various BSDs that support DLT_NULL, but those aren't
necessarily the AF_ values on the machine on which you're building
Ethereal), so we don't need to include it.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@5939 f5534014-38df-0310-8fa8-9805f1628bb7