dmaengine: jz4740: Remove extra check

Remove double check on chan->desc.

Found by Coccinelle.
Signed-off-by: NTapasweni Pathak <tapaswenipathak@gmail.com>
Acked-by: NJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

drivers/dma/dma-jz4740.c

@@ -343,7 +343,7 @@ static void jz4740_dma_chan_irq(struct jz4740_dmaengine_chan *chan)
 {
 	spin_lock(&chan->vchan.lock);
 	if (chan->desc) {
-		if (chan->desc && chan->desc->cyclic) {
+		if (chan->desc->cyclic) {
 			vchan_cyclic_callback(&chan->desc->vdesc);
 		} else {
 			if (chan->next_sg == chan->desc->num_sgs) {