staging: comedi: cb_pcidas: fix comments in *_cmdtest functions

Remove some cut-and-paste comments from the skel driver in the
*_cmdtest functions. Shorten some others to fix the checkpatch.pl
complaints about WARNING: line over 80 characters.

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>