firmware: vpd: remove platform driver

There is no reason why VPD should register platform device and driver,
given that we do not use their respective kobjects to attach attributes,
nor do we need suspend/resume hooks, or any other features of device
core.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>