Fix a bug where fallback from AF_INET6 to AF_INET would not work properly...

Fix a bug where fallback from AF_INET6 to AF_INET would not work properly together with relative search; if you had a search path of .a.com and .b.com, and foo.a.com would return ARES_ENODATA and foo.b.com would return ARES_ENOTFOUND, the lookup would not properly retry with AF_INET as it forgot the first ARES_ENODATA.