not posix or anything and thus c-ares failed to build on hurd (and possibly
elsewhere). The define was also somewhat artificially used in the windows
port. Now, I instead rewrote the use of gethostbyname to enlarge the host
name buffer in case of need and totally avoid the use of the MAXHOSTNAMELEN
define. I thus also removed the defien from the namser.h file where it was
once added for the windows build.
I also fixed init_by_defaults() function to not leak memory in case if
error.
Basically in loops like handle_errors(), 'query->next' was assigned a local
variable and then query was referenced after the memory was freed by
next_server(). I've changed that so next_server() and end_query() returns the
next query. So callers should use this ret-value.
The next problem was that 'server->tcp_buffer_pos' had a random value at entry
to 1st recv() (luckily causing Winsock to return ENOBUFS).
I've also added a ares_writev() for Windows to streamline the code
a bit more.