staging: comedi: mf6x4: refactor block comment

Refactor this block comment to fix the checkpatch.pl issues:
WARNING: Block comments use * on subsequent lines
WARNING: Block comments use a trailing */ on a separate line

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
 drivers/staging/comedi/drivers/mf6x4.c | 2 +-
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>