Staging: comedi: add vmk80xx USB driver

Staging: comedi: add vmk80xx USB driver

The k80xx module was completely revised again. The update contains the
following new main features:
- support for digital input
- support for digital output
- support for pulse counters
- support up to 16 boards (by the way, the windows driver and the k8055
  library (libk8055) has support for only 4 boards)

The driver can now manage all features what the board has to offer:
- analog input/output
- digital input/output
- pulse counters (read, reset, set debounce time)

I've also fixed some mistaken in the drivers source code/logic.

By testing all of the driver features i got no errors or something else.
The driver works fine....

From: Manuel Gebele <forensixs@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>