fsldma: remove useless use of lock

Accordingly to dma_cookie_status() description locking is not required.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/fsldma.c

@@ -979,15 +979,7 @@ static enum dma_status fsl_tx_status(struct dma_chan *dchan,
 					dma_cookie_t cookie,
 					struct dma_tx_state *txstate)
 {
-	struct fsldma_chan *chan = to_fsl_chan(dchan);
-	enum dma_status ret;
-	unsigned long flags;
-
-	spin_lock_irqsave(&chan->desc_lock, flags);
-	ret = dma_cookie_status(dchan, cookie, txstate);
-	spin_unlock_irqrestore(&chan->desc_lock, flags);
-
-	return ret;
+	return dma_cookie_status(dchan, cookie, txstate);
 }
 
 /*----------------------------------------------------------------------------*/