Revert patches from 2005-10-22 and 2006-06-14 to use event driven

	Revert patches from 2005-10-22 and 2006-06-14 to use event driven
	accept and connect back to using select:
	* fhandler.h (class fhandler_socket): Remove accept_mtx.
	* fhandler_socket.cc (fhandler_socket::fhandler_socket): Drop
	initializing accept_mtx.
	(fhandler_socket::accept): Drop event handling.
	(fhandler_socket.cc (fhandler_socket::connect): Ditto.
	(fhandler_socket::dup): Drop accept_mtx handling.
	(fhandler_socket::listen): Ditto.
	(fhandler_socket::prepare): Ditto.
	(fhandler_socket::release): Ditto.
	(fhandler_socket::close): Ditto.
	* net.cc (cygwin_accept): Revert to calling cygwin_select to
	implement interuptible accept.
	(cygwin_connect): Ditto for connect.