bus: uniphier-system-bus: use devm_platform_ioremap_resource()

Replace the chain of platform_get_resource() and devm_ioremap_resource()
with devm_platform_ioremap_resource().

This allows to remove the local variable for (struct resource *), and
have one function call less.

Link: https://lore.kernel.org/r/20190905032122.26076-1-yamada.masahiro@socionext.comSigned-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/bus/uniphier-system-bus.c

@@ -176,7 +176,6 @@ static int uniphier_system_bus_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct uniphier_system_bus_priv *priv;
-	struct resource *regs;
 	const __be32 *ranges;
 	u32 cells, addr, size;
 	u64 paddr;
@@ -186,8 +185,7 @@ static int uniphier_system_bus_probe(struct platform_device *pdev)
 	if (!priv)
 		return -ENOMEM;
 
-	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	priv->membase = devm_ioremap_resource(dev, regs);
+	priv->membase = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(priv->membase))
 		return PTR_ERR(priv->membase);