sched/fair: Mark sched_init_granularity __init

Function sched_init_granularity() is only called from __init
functions, so mark it __init as well.
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20200406074750.56533-1-songmuchun@bytedance.com

kernel/sched/fair.c

@@ -191,7 +191,7 @@ static void update_sysctl(void)
 #undef SET_SYSCTL
 }
 
-void sched_init_granularity(void)
+void __init sched_init_granularity(void)
 {
 	update_sysctl();
 }