USB: serial: cp210x: add support for ELV TFD500

commit c496ad835c31ad639b6865714270b3003df031f6 upstream.

Add the USB device id for the ELV TFD500 data logger.

Signed-off-by: Andreas Engel <anen-nospam@gmx.net>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>