system_nrt[_freezable]_wq were deprecated by 3b07e9ca ("workqueue:
deprecate system_nrt[_freezable]_wq") and have been deprecated
for a long time. In addition, these are not used anymore. So,
let's remove these functions.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NTejun Heo <tj@kernel.org>