satsuma: 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: Ia99ae5ed4f8526eb9da1adceab4745a334e2f9c2
satsuma: Fix leds & backlight configuration on boot

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

Change-Id: I645106efa6b548d3b34bafd5203ea02ea402fa52