video: mdss: Sunlight readability enhancement support

 * This hardware supports a postprocessing mode which improves
   readbility in bright sunlight. Add support for enabling
   this mode when the backlight value crosses a threshold.
 * Enable the feature using /sys/class/graphics/fb0/sre
 * Also add a max backlight level for using CABC. It's not
   effective at full brightness and causes too much visible
   distortion with many images.

Change-Id: I213eb5d91e526c80a0dc88e6e05e6d6f35841fdf
sched: Rollback upstream backport

 * There are some stability issues under certain loads with this
   patchset. Rollback until we can revisit.

Revert "[backport] sched_rt: Upstream fixes"

This reverts commit 3aef4fdd36c3db6f5df88629ab0a9d6c42bae26c.

Revert "[backport] sched: Misc upstream scheduler improvements"

This reverts commit fa16d20f1c90bb0d7955b194d450891de680494e.

Revert "[backport]: sched: Load-based CPU boosting"

This reverts commit 54d5731ffe5a109691de3f61eeda14bd42942325.

Revert "sched: Remove get_online_cpus() usage"

This reverts commit 86b047357013e1d5c5547fd6d466dd75b90afc81.

Change-Id: I8bb638023a95df7ae7a44b06017c0190985e3f22