Diff reduce with upstream by taking diff hunks that were contributed back

Fix coverity issues with contrib/netbsd-tests/lib/libc/sys/t_connect.c

- Ensure socket(2) calls succeed
- Don't leak slist allocated by earlier socket(2) call

MFC after: 2 weeks
CID: 976773, 1251405
Reported by: Coverity
Sponsored by: EMC / Isilon Storage Division

Add sys/socket.h #include for bind(2), et al

Sponsored by: EMC / Isilon Storage Division