acpu: show a useful warn message

Signed-off-by: Dennis Rassmann <showp1984@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
Revert "mpdecision: don't use sleep, cancel/resume wq instead"

This reverts commit 4b6f8555481d2c5049eb7cb496283749ed7cd7ca.

Signed-off-by: Lens-F <tnoah12@gmail.com>