* cygwin.din: Export freeifaddrs, getifaddrs.
* fhandler_socket.cc (fhandler_socket::ioctl): Drop SOCKET parameter
from get_ifconf.
* net.cc: Include ifaddrs.h.
(in_are_prefix_equal): Match addresses in network byte order.
(ip_addr_prefix): Convert address into host byte order before
testing with IN_LOOPBACK.
(struct ifall): Define.
(get_xp_ifs): Replace get_xp_ifconf. Return struct ifall array.
(get_2k_ifs): Ditto, replace get_2k_ifconf.
(get_nt_ifs): Ditto, replace get_nt_ifconf.
(getifaddrs): New function.
(freeifaddrs): New function.
(get_ifconf): Call matching get_XX_ifs function and create
ifc content from here. Drop lo fake since it's now in get_nt_ifs.
* posix.sgml: Add freeifaddrs and getifaddrs to list of implemented
BSD functions.
* wincap.h (wincapc::has_broken_if_oper_status): New element.
* wincap.cc: Implement above element throughout.
* include/ifaddrs.h: New file.
* include/cygwin/version.h: Bump API minor number.
