staging: comedi: adv_pci_dio: move and rename enum hw_cards_id

For aesthetics, move this enum after the register defines and rename
it to have namespace associated with the driver.

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>