Staging: comedi: s626: fix comment issue

This fixes up a WARNING: 'Block comments use a trailing */ on a
separate line'found by the checkpatch.pl tool.
Signed-off-by: Ravishankar Karkala Mallikarjunayya <ravishankarkm32@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>