Pin sched group of service processes with binding flag SLTA at top

...even if the device is asleep, for better performance.

Also limit the use of this flag to the bindings from system and
persistent apps only, any uses in the bindings from other apps will
be no op.

Bug: 184173267
Test: atest MockingOomAdjusterTests
Test: Manual - Check dumpsys output
Change-Id: I930d42e8c53cff56efe85e1755c7c3145ea884af