crypto: amlogic - Fix the parameter of dma_unmap_sg()

For function dma_unmap_sg(), the <nents> parameter should be number of
elements in the scatterlist prior to the mapping, not after the mapping.
So fix this usage.
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/amlogic/amlogic-gxl-cipher.c

@@ -236,10 +236,10 @@ static int meson_cipher(struct skcipher_request *areq)
 	dma_unmap_single(mc->dev, phykeyiv, keyivlen, DMA_TO_DEVICE);
 
 	if (areq->src == areq->dst) {
-		dma_unmap_sg(mc->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
+		dma_unmap_sg(mc->dev, areq->src, sg_nents(areq->src), DMA_BIDIRECTIONAL);
 	} else {
-		dma_unmap_sg(mc->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
-		dma_unmap_sg(mc->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
+		dma_unmap_sg(mc->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
+		dma_unmap_sg(mc->dev, areq->dst, sg_nents(areq->dst), DMA_FROM_DEVICE);
 	}
 
 	if (areq->iv && ivsize > 0) {