[display] Do not disable PSM brightness on setting change. Fixes JB#44169
[display] Do not disable PSM brightness on setting change. Fixes JB#44169

Changing display brightness setting while Power Save Mode is active
partially disables display dimming due to PSM.

Use common function for acting on both PSM activation/deactivation and
brightness setting changes.

Also refactor code related to CABC mode overriding while in PSM.

Signed-off-by: Simo Piiroinen <6d5e5360bed3d486f7d9fb26b0f737f7d4fd45ee@jollamobile.com>

spiiroin/mce,spiiroin/mce,spiiroin/mce,spiiroin/mce