sched/fair: Fix need_idle argument in sched_task_util trace point

fbt_env.need_idle (int type) must be passed instead of
need_idle (bool) to sched_task_util trace point to record
the prefer_spread based idle wakeups.

Change-Id: I8e5a46764d288a325c4469e402f79ea2b4f7fb20
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>