Input: lm8323 - rely on device core to create kp_disable attribute

Device core now has facilities to create driver-specific device attributes
as part of driver probing, use them.

Link: https://lore.kernel.org/r/20230724052901.350240-1-dmitry.torokhov@gmail.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>