sched: tune: Add schedtune+WALT snapshot

This snapshot is taken from msm-4.9 as of commit 57637bbc4fb6537
(Revert "ANDROID: sched/tune: Initialize raw_spin_lock
in boosted_groups").

Change-Id: Ie624026a428c13a6a1f9a1cee259bf5cdd59860a
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
[satyap@codeaurora.org: resolve merge conflicts & uncomment
code for compilation]
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>