workqueue: use percpu allocator for cwq on UP
workqueue: use percpu allocator for cwq on UP

I notice that the commit bbddff makes percpu allocator can work on UP,
So we don't need the magic way for UP.

Signed-off-by: Lai Jiangshan <4c9eb49378914b743bdd32292c04df29b820d73e@cn.fujitsu.com>
Signed-off-by: Tejun Heo <546b05909706652891a87f7bfe385ae147f61f91@kernel.org>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs