staging: comedi: pcmmio: remove subdevice private data
Only subdevice[2], the dio interrupt subdevice, uses the subdevice private data.
Move the members from struct pcmmio_subdev_private to struct pcmmio_private and
remove the subdevice private data. This also allows removing the allocation and
freeing of devpriv->sprivs.
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>