mei: stop the stall timer worker if not needed

The stall timer worker checks periodically if there is a stalled i/o
transaction. The issue with the current implementation is that the timer
is ticking also when there is no pending i/o transaction.
This patch provides a simple change that prevents rescheduling
of the delayed work when there is no pending i/o.

Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index f7c8dfd..9a9c248 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -94,7 +94,7 @@
 	cancel_work_sync(&dev->reset_work);
 	cancel_work_sync(&dev->bus_rescan_work);
 
-	cancel_delayed_work(&dev->timer_work);
+	cancel_delayed_work_sync(&dev->timer_work);
 }
 EXPORT_SYMBOL_GPL(mei_cancel_work);