msm_perf: perf data collection at 300ms interval

Registered for callback from scheduler to get big_nr
and top app load for each sched window(20ms). Collecting
the data for 15 windows(300ms) and after aggregating the
data updating the same to sysfs node

sys/module/msm_performance/notify/aggr_top_load
sys/module/msm_performance/notify/aggr_big_nr

This data will be used by game optimization feature in
learning module to decide the number of cpu core needed.

Change-Id: I4b3def013cefd5fa9cfd5388793e41a5aca295a0
Signed-off-by: Nikhil Kumar Kansal <nkansal@codeaurora.org>