pinctrl: renesas: rzn1: Fix possible null-ptr-deref in sh_pfc_map_resources()

It will cause null-ptr-deref when using 'res', if platform_get_resource()
returns NULL, so move using 'res' after devm_ioremap_resource() that
will check it to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220429082637.1308182-2-yangyingliang@huawei.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

drivers/pinctrl/renesas/pinctrl-rzn1.c

@@ -865,17 +865,15 @@ static int rzn1_pinctrl_probe(struct platform_device *pdev)
 	ipctl->mdio_func[0] = -1;
 	ipctl->mdio_func[1] = -1;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	ipctl->lev1_protect_phys = (u32)res->start + 0x400;
-	ipctl->lev1 = devm_ioremap_resource(&pdev->dev, res);
+	ipctl->lev1 = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 	if (IS_ERR(ipctl->lev1))
 		return PTR_ERR(ipctl->lev1);
+	ipctl->lev1_protect_phys = (u32)res->start + 0x400;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
-	ipctl->lev2_protect_phys = (u32)res->start + 0x400;
-	ipctl->lev2 = devm_ioremap_resource(&pdev->dev, res);
+	ipctl->lev2 = devm_platform_get_and_ioremap_resource(pdev, 1, &res);
 	if (IS_ERR(ipctl->lev2))
 		return PTR_ERR(ipctl->lev2);
+	ipctl->lev2_protect_phys = (u32)res->start + 0x400;
 
 	ipctl->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(ipctl->clk))