Staging: comedi: fix style for multi-line comments in cb_pcidas64.c

This patch reformat multi-line comments which are not properly written
according to the kernel coding style in cb_pcidas64.c

Signed-off-by: Amaury Denoyelle <amaury.denoyelle@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>