cpuset: remove redundant check in cpuset_cpus_allowed_fallback()

task_cs() will never return NULL.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

kernel/cpuset.c

@@ -2253,8 +2253,7 @@ void cpuset_cpus_allowed_fallback(struct task_struct *tsk)
 
 	rcu_read_lock();
 	cs = task_cs(tsk);
-	if (cs)
-		do_set_cpus_allowed(tsk, cs->cpus_allowed);
+	do_set_cpus_allowed(tsk, cs->cpus_allowed);
 	rcu_read_unlock();
 
 	/*