staging: fieldbus: anybus: Make remove callback return void

The driver core ignores the return value of struct bus_type::remove()
because there is only little that can be done. To simplify the quest to
make this function return void, let struct
anybuss_client_driver::remove() return void, too. All users already
unconditionally return 0, this commit makes it obvious that returning an
error code is a bad idea.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210505202923.198607-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fieldbus/anybuss/anybuss-client.h

@@ -32,7 +32,7 @@ struct anybuss_client {
 struct anybuss_client_driver {
 	struct device_driver driver;
 	int (*probe)(struct anybuss_client *adev);
-	int (*remove)(struct anybuss_client *adev);
+	void (*remove)(struct anybuss_client *adev);
 	u16 anybus_id;
 };
 

drivers/staging/fieldbus/anybuss/hms-profinet.c

@@ -190,12 +190,11 @@ static int profinet_probe(struct anybuss_client *client)
 	return 0;
 }
 
-static int profinet_remove(struct anybuss_client *client)
+static void profinet_remove(struct anybuss_client *client)
 {
 	struct profi_priv *priv = anybuss_get_drvdata(client);
 
 	fieldbus_dev_unregister(&priv->fbdev);
-	return 0;
 }
 
 static struct anybuss_client_driver profinet_driver = {

drivers/staging/fieldbus/anybuss/host.c

@@ -1194,7 +1194,8 @@ static int anybus_bus_remove(struct device *dev)
 		to_anybuss_client_driver(dev->driver);
 
 	if (adrv->remove)
-		return adrv->remove(to_anybuss_client(dev));
+		adrv->remove(to_anybuss_client(dev));
+
 	return 0;
 }