Revert "workqueue: Backport from upstream Part II of II"

This reverts commit ed774aaf7e3c6d335e73d3660cae23eaebc8d59d.
Revert "workqueue: Backport from upstream Part I"

This reverts commit 4dbb4816c8fbe79c199757fb038a33b2135c729b.
Revert " nohz: stat: Fix CPU idle time accounting"

This reverts commit 6ddec32ea2b79d20bb41f6843a1ad3be9bc7ed2d.
What?