gpio: cs5535: Switch to using managed resources with devm_

This change switches to devm_request_region to request region
and hence simplifies the module unload and does away with
release_region in remove function.

Cc: [e-mail]
Signed-off-by: Pramod Gurav <[e-mail]>
Reviewed-by: Alexandre Courbot <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/gpio/gpio-cs5535.c

···
 		goto done;
 	}
 
-	if (!request_region(res->start, resource_size(res), pdev->name)) {
+	if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
+				 pdev->name)) {
 		dev_err(&pdev->dev, "can't request region\n");
 		goto done;
 	}
···
 	/* finally, register with the generic GPIO API */
 	err = gpiochip_add(&cs5535_gpio_chip.chip);
 	if (err)
-		goto release_region;
+		goto done;
 
 	return 0;
 
-release_region:
-	release_region(res->start, resource_size(res));
 done:
 	return err;
 }
 
 static int cs5535_gpio_remove(struct platform_device *pdev)
 {
-	struct resource *r;
-
 	gpiochip_remove(&cs5535_gpio_chip.chip);
 
-	r = platform_get_resource(pdev, IORESOURCE_IO, 0);
-	release_region(r->start, resource_size(r));
 	return 0;
 }