workqueue: Changes for v7.2

- Continued progress toward making alloc_workqueue() unbound by default:
  more callers converted to WQ_PERCPU / system_percpu_wq / system_dfl_wq,
  and new warnings for queues that use neither WQ_PERCPU nor WQ_UNBOUND
  or the legacy system_wq / system_unbound_wq.

- Misc: drop the now-trivial apply_wqattrs_lock()/unlock() wrappers,
  forbid the TEST_WORKQUEUE benchmark from being built-in, and fix a
  spurious pointer level in the worker debug-dump path.

drm/bridge: anx7625: Add WQ_PERCPU add to alloc_workqueue

This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

   commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq")
   commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag")

The refactoring is going to alter the default behavior of
alloc_workqueue() to be unbound by default.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU. For more details see the Link tag below.

In order to keep alloc_workqueue() behavior identical, explicitly request
WQ_PERCPU.

Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>