extcon: max8997: Use devm_extcon_dev_register()

Use the resource-managed extcon device register function (i.e.
devm_extcon_dev_register()) instead of extcon_dev_register(). If extcon device
is attached with this function, that extcon device is automatically unregistered
on driver detach. That reduces tiresome managing code.

Signed-off-by: Sangjung Woo <sangjung.woo@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

drivers/extcon/extcon-max8997.c

@@ -709,7 +709,7 @@ static int max8997_muic_probe(struct platform_device *pdev)
 	info->edev->name = DEV_NAME;
 	info->edev->dev.parent = &pdev->dev;
 	info->edev->supported_cable = max8997_extcon_cable;
-	ret = extcon_dev_register(info->edev);
+	ret = devm_extcon_dev_register(&pdev->dev, info->edev);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register extcon device\n");
 		goto err_irq;
@@ -790,8 +790,6 @@ static int max8997_muic_remove(struct platform_device *pdev)
 		free_irq(muic_irqs[i].virq, info);
 	cancel_work_sync(&info->irq_work);
 
-	extcon_dev_unregister(info->edev);
-
 	return 0;
 }