DO NOT MERGE: Revert "Revert "Add libprocessgroup dependency and fix sched_policy include""

This reverts commit 7194e6da.

Reason for revert: AOSP is fixed with new vendor image

Change-Id: I15797a30abcc304379db05bec1b25a0bd95b2ff4
Signed-off-by: Suren Baghdasaryan <surenb@google.com>