staging: comedi: adl_pci9111: use 8253 helper functions

The timer on this board is a standard 8254 compatible counter/timer.
Instead of open-coding the 8254 timer io, use the helper functions
provided by 8253.h.

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