dmaengine: xilinx_dma: Remove desc_callback_valid check

In descriptor cleanup the call to desc_callback_valid can be safely
removed as both callback pointers i.e callback_result and callback
are anyway checked in invoke(). There is no much benefit in having
redundant checks.
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Reviewed-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-2-git-send-email-radhey.shyam.pandey@xilinx.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/xilinx/xilinx_dma.c

@@ -832,11 +832,9 @@ static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
 
 		/* Run the link descriptor callback function */
 		dmaengine_desc_get_callback(&desc->async_tx, &cb);
-		if (dmaengine_desc_callback_valid(&cb)) {
-			spin_unlock_irqrestore(&chan->lock, flags);
-			dmaengine_desc_callback_invoke(&cb, NULL);
-			spin_lock_irqsave(&chan->lock, flags);
-		}
+		spin_unlock_irqrestore(&chan->lock, flags);
+		dmaengine_desc_callback_invoke(&cb, NULL);
+		spin_lock_irqsave(&chan->lock, flags);
 
 		/* Run any dependencies, then free the descriptor */
 		dma_run_dependencies(&desc->async_tx);