dmaengine: fsldma: convert callback to helper function

This is in preperation of moving to a callback that provides results to the
callback for the transaction. The conversion will maintain current behavior
and the driver must convert to new callback mechanism at a later time in
order to receive results.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Li Yang <leoli@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/fsldma.c

@@ -517,11 +517,7 @@ static dma_cookie_t fsldma_run_tx_complete_actions(struct fsldma_chan *chan,
 		ret = txd->cookie;
 
 		/* Run the link descriptor callback function */
-		if (txd->callback) {
-			chan_dbg(chan, "LD %p callback\n", desc);
-			txd->callback(txd->callback_param);
-		}
-
+		dmaengine_desc_get_callback_invoke(txd, NULL);
 		dma_descriptor_unmap(txd);
 	}