* autoload.cc (WNetGetProviderNameA): Define.

	* autoload.cc (WNetGetProviderNameA): Define.
	(WNetGetResourceParentA): Remove.
	* fhandler_netdrive.cc (struct net_hdls): New structure to keep
	WNet handles.  Stored in dir->__handle throughout.
	(thread_netdrive): Rewrite to enumerate all servers in all accessible
	domains and workgroups.
	(fhandler_netdrive::readdir): Simplify toplevel code.  Lowercase all
	server names in toplevel.
	(fhandler_netdrive::rewinddir): Close all WNet handles and free
	net_hdls structure.