staging: comedi: pcl711: remove 'is_8112' from boardinfo

This member in the boardinfo is redundant. All the 8112 style boards
have > 8 analog input channels (16 actually). We can use that information
instead and remove the extra boardinfo.

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>