dmaengine: zynqmp_dma: fix lockdep warning in tasklet

The tasklet that handles the completed dma transfers uses spin_unlock
for unlocking a spin lock that was previously locked with
spin_lock_irqsave.

This caused the following lockdep warning about an inconsistent lock
state:

	inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.

We must use spin_lock_irqsave, because it is possible to queue DMA
transfers from an irq handler.

Replace the spin_unlock and spin_lock by spin_unlock_irqrestore and
spin_lock_irqsave.
Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Link: https://lore.kernel.org/r/20210826094742.1302009-8-m.tretter@pengutronix.deSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/xilinx/zynqmp_dma.c

@@ -611,9 +611,9 @@ static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan)
 		callback = desc->async_tx.callback;
 		callback_param = desc->async_tx.callback_param;
 		if (callback) {
-			spin_unlock(&chan->lock);
+			spin_unlock_irqrestore(&chan->lock, irqflags);
 			callback(callback_param);
-			spin_lock(&chan->lock);
+			spin_lock_irqsave(&chan->lock, irqflags);
 		}
 
 		/* Run any dependencies, then free the descriptor */