* cygserver_ipc (class ipc_retval): Add ssize_t member to anonymous union.
(ipc_retval::operator =): Add ssize_t variant for x86_64.
* fhandler_floppy.cc (fhandler_dev_floppy::raw_write): Change return
type to ssize_t to match fhandler.h.
* fhandler_socket.cc (fhandler_socket::readv): Ditto.
(fhandler_socket::write): Ditto.
(fhandler_socket::writev): Ditto.
(fhandler_socket::sendmsg): Ditto.