Added AI_V4MAPPED and AI_ALL to getaddrinfo.c

[Philip Homburg]

Hi,

I'm using FreeBSD library code for some other project and I needed AI_V4MAPPED
and AI_ALL for getaddrinfo. So I wrote some code to support these features.

Is anybody interested in this? I can give you patch to an older version of
getaddrinfo.c. It needs some work, in particular restoring some partial
support for AI_V4MAPPED and AI_ALL that was removed a couple of years ago.