xinetd: socket bind: Invalid argument (errno = 22) when using USERID on ipv6

Use right size of addresses in bind() call. Also use getpeername addresses when
connecting to ident service to prevent address family mismatch between socket(),
bind() and connect() calls.

---
Christian Schoenebeck via github pull request #205:
Reported for a long time in the web. Still exists in the current sources.
Already reported and offert on TRAC Ticket #15821.

You can find a lot of entries on "Google" about the reported problem.
I got the same error on my WNDR3800 and von VirtualBox X86.
I copied the patch to my local trunk build system and recompiled.
The problem was fixed.

Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>
Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>