tracing: Restore original format of sched events

The original format for sched_stat_iowait and sched_stat_sleep:

  $ cat events/sched/sched_stat_iowait/format
  ...
  print fmt: "comm=%s pid=%d delay=%Lu [ns]", ...
  $ cat events/sched/sched_stat_sleep/format
  ...
  print fmt: "comm=%s pid=%d delay=%Lu [ns]", ...

But commit commit 75ec29ab
("tracing: Convert some sched trace events to DEFINE_EVENT and
_PRINT") broke the format:

  $ cat events/sched/sched_stat_iowait/format
  print fmt: "task: %s:%d iowait: %Lu [ns]", ...
  $ cat events/sched/sched_stat_sleep/format
  print fmt: "task: %s:%d sleep: %Lu [ns]", ...

No change in functionality.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E2951.9050800@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/trace/events/sched.h

@@ -355,23 +355,17 @@ DEFINE_EVENT(sched_stat_template, sched_stat_wait,
  * Tracepoint for accounting sleep time (time the task is not runnable,
  * including iowait, see below).
  */
-DEFINE_EVENT_PRINT(sched_stat_template, sched_stat_sleep,
-		   TP_PROTO(struct task_struct *tsk, u64 delay),
-		   TP_ARGS(tsk, delay),
-		   TP_printk("task: %s:%d sleep: %Lu [ns]",
-			     __entry->comm, __entry->pid,
-			     (unsigned long long)__entry->delay));
+DEFINE_EVENT(sched_stat_template, sched_stat_sleep,
+	     TP_PROTO(struct task_struct *tsk, u64 delay),
+	     TP_ARGS(tsk, delay));
 
 /*
  * Tracepoint for accounting iowait time (time the task is not runnable
  * due to waiting on IO to complete).
  */
-DEFINE_EVENT_PRINT(sched_stat_template, sched_stat_iowait,
-		   TP_PROTO(struct task_struct *tsk, u64 delay),
-		   TP_ARGS(tsk, delay),
-		   TP_printk("task: %s:%d iowait: %Lu [ns]",
-			     __entry->comm, __entry->pid,
-			     (unsigned long long)__entry->delay));
+DEFINE_EVENT(sched_stat_template, sched_stat_iowait,
+	     TP_PROTO(struct task_struct *tsk, u64 delay),
+	     TP_ARGS(tsk, delay));
 
 /*
  * Tracepoint for accounting runtime (time the task is executing