mmc: fix "prev->state: 2 != TASK_RUNNING??" problem on SD/MMC card removal

Currently on SD/MMC card removal the system exhibits the following message (the platform is ARM Versatile):

    prev->state: 2 != TASK_RUNNING??
    mmcqd/762[CPU#0]: BUG in __schedule at linux-2.6/kernel/sched.c:3826

(akpm: someone tried to fix this, but it's still wrong)
Signed-off-by: NVitaly Wool <vitalywool@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

drivers/mmc/mmc_queue.c

@@ -78,8 +78,10 @@ static int mmc_queue_thread(void *d)
 		spin_unlock_irq(q->queue_lock);
 
 		if (!req) {
-			if (kthread_should_stop())
+			if (kthread_should_stop()) {
+				set_current_state(TASK_RUNNING);
 				break;
+			}
 			up(&mq->thread_sem);
 			schedule();
 			down(&mq->thread_sem);