hwrng: iproc-rng200 - Use devm_platform_ioremap_resource() in iproc_rng200_probe()

Simplify this function implementation by using a known wrapper function.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/iproc-rng200.c

@@ -181,7 +181,6 @@ static void iproc_rng200_cleanup(struct hwrng *rng)
 static int iproc_rng200_probe(struct platform_device *pdev)
 {
 	struct iproc_rng200_dev *priv;
-	struct resource *res;
 	struct device *dev = &pdev->dev;
 	int ret;
 
@@ -190,13 +189,7 @@ static int iproc_rng200_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	/* Map peripheral */
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_err(dev, "failed to get rng resources\n");
-		return -EINVAL;
-	}
-
-	priv->base = devm_ioremap_resource(dev, res);
+	priv->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(priv->base)) {
 		dev_err(dev, "failed to remap rng regs\n");
 		return PTR_ERR(priv->base);