staging: comedi: addi_apci_1564: board has 32 digital outputs

This board always has 32 digital outputs.  Remove the test when
initializing the subdevice.

Also, since this board is the only one supported by this driver, remove
the boardinfo about the digital outputs and just use the data directly in
the subdevice init.

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