staging: comedi: amplc_pc263: tidy up comedi_driver definition

For aesthetics, add some whitespace to the comedi_driver definition.
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>