staging: comedi: pcl812: remove 0/NULL initialzation in boardinfo

The unlisted members in the boardinfo declaration will default to 0/NULL.

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>