unix: fix uv_freeaddrinfo() segfault on sunos
unix: fix uv_freeaddrinfo() segfault on sunos

The system freeaddrinfo() on SunOS does not handle NULL values graciously.

unknownbrackets/maxcso,urbit/archaeology2,urbit/archaeology2,urbit/archaeology2,unknownbrackets/maxcso,urbit/archaeology2,unknownbrackets/maxcso,urbit/archaeology2,urbit/archaeology2,urbit/archaeology2,urbit/archaeology2,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,urbit/archaeology2