staging: comedi: addi-data: remove i_pci_card_free()

This function calls comedi_pci_disable() to disable the pci
device when detached. It's only called from i_ADDI_Detach().
Move the code there and delete the function.

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>