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

This reverts commit c5e0fdab.

Reason for revert: AOSP is fixed with new vendor image

Change-Id: Iae858f743fbd7e4f58f89b8ba0498f10f6ae0e81
Signed-off-by: Suren Baghdasaryan <surenb@google.com>