iommu/mtk: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230321084125.337021-8-u.kleine-koenig@pengutronix.de
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: Uwe Kleine-König

drivers/iommu/mtk_iommu.c

@@ -1316,7 +1316,7 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int mtk_iommu_remove(struct platform_device *pdev)
+static void mtk_iommu_remove(struct platform_device *pdev)
 {
 	struct mtk_iommu_data *data = platform_get_drvdata(pdev);
 	struct mtk_iommu_bank_data *bank;
@@ -1338,7 +1338,6 @@ static int mtk_iommu_remove(struct platform_device *pdev)
 			continue;
 		devm_free_irq(&pdev->dev, bank->irq, bank);
 	}
-	return 0;
 }
 
 static int __maybe_unused mtk_iommu_runtime_suspend(struct device *dev)
@@ -1595,7 +1594,7 @@ static const struct of_device_id mtk_iommu_of_ids[] = {
 
 static struct platform_driver mtk_iommu_driver = {
 	.probe	= mtk_iommu_probe,
-	.remove	= mtk_iommu_remove,
+	.remove_new = mtk_iommu_remove,
 	.driver	= {
 		.name = "mtk-iommu",
 		.of_match_table = mtk_iommu_of_ids,