This simple event implemention can only support exclusive waiting
at same time. It mainly used by thread who want to wait for special event
happens.
Thread A who want to wait for some events calls
wait_event(struct sched_event *);
Thread B who can give the event signal calls
signal_event(struct sched_event *);
Tracked-On: #4329
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>