staging: comedi: addi_apci_1564: tidy register map defines

This commit performs a final tidying of the register map defines, bringing
them to a state that is ready for merging into addi_apci_1564.c when the
time comes.  Actions performed include:

*Removes the APCI1564_ADDRESS_RANGE macro, which is no longer needed/used.
*Renames the APCI1564_DIGITAL_OP_{VCC,CC}_INTERRUPT_{ENABLE,DISABLE}
macros to shorter names which are more consistent with the digital input
interrupt macros.
*Fixes a typo in a comment (dev>iobase changed to dev->iobase).
*Renames the APCI1564_TCW_* macros to APCI1564_COUNTER_* names to more
accurately reflect that they are only offsets to counter registers (since
only the counters are offset from dev->iobase).

Signed-off-by: Chase Southwood <chase.southwood@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengraver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>