[ Upstream commit 0ed2a005 ]

In case create_singlethread_workqueue fails, the fix free the
hardware and returns NULL to avoid NULL pointer dereference.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>