Vaio Pro uses a different handle and doesn't support all the options as
other models (only S5 setting v/s S3/4/5).

Minor code rework to generalize functions by Mattia Dongili.
Signed-off-by: Javier Achirica <jachirica@gmail.com>
Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>