USB: serial: cp210x: disable interface on errors in open

Try to disable the serial interface in the unlikely event that generic
open() fails.

Link: https://lore.kernel.org/r/20200713105517.27796-2-johan@kernel.org
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>