comedi: drivers: ni_tio: Fix slightly broken kernel-doc and demote others

Fixes the following W=1 kernel build warning(s):

drivers/staging/comedi/drivers/ni_tio.c:1515: warning: Function parameter or member 'counter_dev' not described in 'ni_tio_get_routing'
drivers/staging/comedi/drivers/ni_tio.c:1515: warning: Function parameter or member 'dest' not described in 'ni_tio_get_routing'
drivers/staging/comedi/drivers/ni_tio.c:1515: warning: expecting prototype for Retrieves the register value of the current source of the output selector for(). Prototype was for ni_tio_get_routing() instead
drivers/staging/comedi/drivers/ni_tio.c:1544: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
drivers/staging/comedi/drivers/ni_tio.c:1584: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst

Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mori Hess <fmhess@users.sourceforge.net>
Cc: "J.P. Mellor" <jpmellor@rose-hulman.edu>
Cc: Herman.Bruyninckx@mech.kuleuven.ac.be
Cc: Wim.Meeussen@mech.kuleuven.ac.be
Cc: Klaas.Gadeyne@mech.kuleuven.ac.be
Cc: Comedi <comedi@comedi.org>
Cc: linux-staging@lists.linux.dev
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210520122538.3470259-4-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: comedi: move out of staging directory

The comedi code came into the kernel back in 2008, but traces its
lifetime to much much earlier. It's been polished and buffed and
there's really nothing preventing it from being part of the "real"
portion of the kernel.

So move it to drivers/comedi/ as it belongs there.

Many thanks to the hundreds of developers who did the work to make this
happen.

Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Link: https://lore.kernel.org/r/YHauop4u3sP6lz8j@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>