staging: comedi: cb_das16_cs: convert driver to use the comedi_8254 module

The hardware supported by this drive has an 8254 timer. Currently this driver
does not use the timer functions.

For aesthetics, use the comedi_8254 module to provide support for the 8254
timer. This will ensure that the counters are all reset and make it easier
to add functionality later.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>