watchdog: simplify platform_get_resource_byname/devm_ioremap_resource

Remove unneeded error handling on the result of a call to
platform_get_resource_byname when the value is passed to devm_ioremap_resource.

A simplified version of the semantic patch that makes this change is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression pdev,res,e,e1;
expression ret != 0;
identifier l;
@@

  res = platform_get_resource_byname(...);
- if (res == NULL) { ... \(goto l;\|return ret;\) }
  e = devm_ioremap_resource(e1, res);
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

drivers/watchdog/ar7_wdt.c

@@ -280,11 +280,6 @@ static int ar7_wdt_probe(struct platform_device *pdev)
 
 	ar7_regs_wdt =
 		platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
-	if (!ar7_regs_wdt) {
-		pr_err("could not get registers resource\n");
-		return -ENODEV;
-	}
-
 	ar7_wdt = devm_ioremap_resource(&pdev->dev, ar7_regs_wdt);
 	if (IS_ERR(ar7_wdt))
 		return PTR_ERR(ar7_wdt);