staging: comedi: c6xdigio: tidy up the multi-line comments

Reformat the multi-line comments at the beginning of the code to
follow the CodingStyle.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>