iyokan: Remove obsolete ALS configuration

Also set button_backlight current on pre_hw_config.sh to avoid too bright recovery indication.

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: I312948526a8ea3a170b2bdc3c76c3f4c9f55ff5f
iyokan: Fix leds & backlight configuration on boot

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: Ie12bc866309d40fff31634719ffc3f858d412ea3