fsldma: Add a completed cookie updated action in DMA finish interrupt.

The patch 'fsldma: do not cleanup descriptors in hardirq context'
(commit 222ccf9) removed descriptors
cleanup function to tasklet but the completed cookie do not updated.
Thus, the DMA controller will get lots of duplicated transfer
interrupts. Just make a completed cookie update in interrupt handler.
And keep other cleanup jobs in tasklet function.

Tested-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Zhang Wei <wei.zhang@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/fsldma.c

@@ -539,7 +539,6 @@ static void fsl_chan_ld_cleanup(struct fsl_dma_chan *fsl_chan)
 
 	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 
-	fsl_dma_update_completed_cookie(fsl_chan);
 	dev_dbg(fsl_chan->dev, "chan completed_cookie = %d\n",
 			fsl_chan->completed_cookie);
 	list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
@@ -710,6 +709,7 @@ static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
 		dev_dbg(fsl_chan->dev, "event: clndar %p, nlndar %p\n",
 			(void *)get_cdar(fsl_chan), (void *)get_ndar(fsl_chan));
 		stat &= ~FSL_DMA_SR_EOSI;
+		fsl_dma_update_completed_cookie(fsl_chan);
 	}
 
 	/* If it current transfer is the end-of-transfer,