staging: mt7621-pinctrl: Test devm_kzalloc for failure while improving the code

This patch tests the return of devm_kzalloc for failure and
improves the code.
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-pinctrl/pinctrl-rt2880.c

@@ -350,7 +350,6 @@ static int rt2880_pinmux_probe(struct platform_device *pdev)
 	for_each_compatible_node(np, NULL, "ralink,rt2880-gpio") {
 		const __be32 *ngpio, *gpiobase;
 		struct pinctrl_gpio_range *range;
-		char *name;
 
 		if (!of_device_is_available(np))
 			continue;
@@ -362,9 +361,10 @@ static int rt2880_pinmux_probe(struct platform_device *pdev)
 			return -EINVAL;
 		}
 
-		range = devm_kzalloc(p->dev, sizeof(*range) + 4, GFP_KERNEL);
-		range->name = name = (char *)&range[1];
-		sprintf(name, "pio");
+		range = devm_kzalloc(p->dev, sizeof(*range), GFP_KERNEL);
+		if (!range)
+			return -ENOMEM;
+		range->name = "pio";
 		range->npins = __be32_to_cpu(*ngpio);
 		range->base = __be32_to_cpu(*gpiobase);
 		range->pin_base = range->base;