staging: comedi: addi_apci_3xxx: introduce a local private data definition

The struct addi_private definition from the addi-data "common" code is
very bloated. Introduce a local struct apci3xxx_private that just has
the data needed by this driver.

Add a couple includes that this driver depends on and remove the include
of "addi-data/addi_common.h" since this driver no longer depends on it.

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>