* net.cc (free_char_list): Delete.

* net.cc (free_char_list): Delete.
(dup_addr_list): Delete.
(dup_char_list): Delete.
(free_hostent_ptr): Delete.
(free_protoent_ptr): Delete.
(free_servent_ptr): Delete.
(DWORD_round): New function.
(strlen_round): New function.  Returns strlen rounded up to word size.
(dup_ent): New, generic function to duplicate a {host,proto,serv}ent structure.
(gen_ent): New macro.  Generates a generic dup_{host,proto,serv}ent_ptr
function.
(cygwin_getservbyname): Remove call to free_servent_ptr, pass servent_buf to
dup_servent_ptr.
(cygwin_getservbyport): Ditto.
(cygwin_gethostbyname): Ditto for hostent.
(cygwin_gethostbyaddr): Ditto.
(cygwin_getprotobyname): Ditto for protoent.
(cygwin_getprotobynumber): Ditto.