Staging: comedi: add pcl711 driver

hardware driver for PC-LabCard PCL-711 and AdSys ACL-8112

From: David Schleef <ds@schleef.org>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Janne Jalkanen <jalkanen@cs.hut.fi>
Cc: Eric Bunn <ebu@cs.hut.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>