staging: comedi: ni_mio_cs: remove cs_release()

This function simply calls pcmcia_disable_device(). Remove it and
just call pcmcia_disable_device() where needed.

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>