staging: comedi: addi_apci_3501: rename private data 'i_IobaseAmcc'

Rename this CamelCase member of the private data.

Also, fix the type of the member, it holds a pci_resource_start()
address and should be an unsigned long.

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>