sched: remove redundant code in cpu_cgroup_create()

css will be initialized by cgroup core.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -9088,7 +9088,6 @@ cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp)
 
 	if (!cgrp->parent) {
 		/* This is early initialization for the top cgroup */
-		init_task_group.css.cgroup = cgrp;
 		return &init_task_group.css;
 	}
 
@@ -9097,9 +9096,6 @@ cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp)
 	if (IS_ERR(tg))
 		return ERR_PTR(-ENOMEM);
 
-	/* Bind the cgroup to task_group object we just created */
-	tg->css.cgroup = cgrp;
-
 	return &tg->css;
 }