staging: comedi: ni_daq_700: remove unused pcmcia 'stop' logic

The pcmcia support code in this driver appears to be cut-and-
paste from some other driver. It has code in it to stop the
device during suspend but nothing in the main comedi_driver
uses it.

Remove the 'stop' variable from the pcmcia private data and
all the logic that deals with it.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>