staging: comedi: ni_labpc: tidy up subdevice init

Add some whitespace to the subdevice init.

Remove the unnecessary comment about adding command support to
the analog input subdevice and change the 'maxdata' value to hex
as this is more common in comedi drivers.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>