staging: comedi: addi-data: remove 'irq' from the card data

This information can be found when needed in i_ADDI_Attach() by
using the pci_dev pointer.

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>