trace/events/sched.h: fix duplicated word

Change "It it" to "It is".
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/25305c1d-4ee8-e091-d20f-e700ddad49fd@infradead.org

include/trace/events/sched.h

@@ -91,7 +91,7 @@ DEFINE_EVENT(sched_wakeup_template, sched_waking,
 
 /*
  * Tracepoint called when the task is actually woken; p->state == TASK_RUNNNG.
- * It it not always called from the waking context.
+ * It is not always called from the waking context.
  */
 DEFINE_EVENT(sched_wakeup_template, sched_wakeup,
 	     TP_PROTO(struct task_struct *p),