firmware: zynqmp: 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 ignored (apart
from emitting a warning) 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. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

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: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/b5a82472a6d61608c2cd7728ca364f6c88a821c3.1703693980.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Uwe Kleine-König

drivers/firmware/xilinx/zynqmp.c

@@ -1929,7 +1929,7 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
 	return of_platform_populate(dev->of_node, NULL, NULL, dev);
 }
 
-static int zynqmp_firmware_remove(struct platform_device *pdev)
+static void zynqmp_firmware_remove(struct platform_device *pdev)
 {
 	struct pm_api_feature_data *feature_data;
 	struct hlist_node *tmp;
@@ -1944,8 +1944,6 @@ static int zynqmp_firmware_remove(struct platform_device *pdev)
 	}
 
 	platform_device_unregister(em_dev);
-
-	return 0;
 }
 
 static const struct of_device_id zynqmp_firmware_of_match[] = {
@@ -1962,6 +1960,6 @@ static struct platform_driver zynqmp_firmware_driver = {
 		.dev_groups = zynqmp_firmware_groups,
 	},
 	.probe = zynqmp_firmware_probe,
-	.remove = zynqmp_firmware_remove,
+	.remove_new = zynqmp_firmware_remove,
 };
 module_platform_driver(zynqmp_firmware_driver);