scsi: ufs: core: Reduce the clock scaling latency

Wait at most 20 ms before rechecking the doorbells instead of waiting for a
potentially long time between doorbell checks.

Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/ufs/core/ufshcd.c

@@ -1154,7 +1154,7 @@ static int ufshcd_wait_for_doorbell_clr(struct ufs_hba *hba,
 		}
 
 		spin_unlock_irqrestore(hba->host->host_lock, flags);
-		schedule();
+		io_schedule_timeout(msecs_to_jiffies(20));
 		if (ktime_to_us(ktime_sub(ktime_get(), start)) >
 		    wait_timeout_us) {
 			timeout = true;