sched: change sched_debug's mode to 0444

Impact: change /proc/sched/debug from rw-r--r-- to r--r--r--

/proc/sched_debug is read-only.

Signed-off-by: Li Zefan <[e-mail]>
Acked-by: Peter Zijlstra <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>

kernel/sched_debug.c

···
 {
 	struct proc_dir_entry *pe;
 
-	pe = proc_create("sched_debug", 0644, NULL, &sched_debug_fops);
+	pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
 	if (!pe)
 		return -ENOMEM;
 	return 0;