hwrng: bcm2835 - Fix W=1 unused variable warning

This patch fixes an unused variable warning when this driver is
built with CONFIG_OF=n.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/bcm2835-rng.c

@@ -139,7 +139,6 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
 {
 	const struct bcm2835_rng_of_data *of_data;
 	struct device *dev = &pdev->dev;
-	struct device_node *np = dev->of_node;
 	const struct of_device_id *rng_id;
 	struct bcm2835_rng_priv *priv;
 	int err;
@@ -166,7 +165,7 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
 	priv->rng.cleanup = bcm2835_rng_cleanup;
 
 	if (dev_of_node(dev)) {
-		rng_id = of_match_node(bcm2835_rng_of_match, np);
+		rng_id = of_match_node(bcm2835_rng_of_match, dev->of_node);
 		if (!rng_id)
 			return -EINVAL;