ipack: Handle a driver without remove callback

A driver that only consumes devm-managed resources might well have no
remove callback. Additionally given that the device core ignores the return
value of ipack_bus_remove() stop returning an error code.
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Acked-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Link: https://lore.kernel.org/r/20210207215556.96371-2-uwe@kleine-koenig.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/ipack/ipack.c

@@ -72,10 +72,9 @@ static int ipack_bus_remove(struct device *device)
 	struct ipack_device *dev = to_ipack_dev(device);
 	struct ipack_driver *drv = to_ipack_driver(device->driver);
 
-	if (!drv->ops->remove)
-		return -EINVAL;
+	if (drv->ops->remove)
+		drv->ops->remove(dev);
 
-	drv->ops->remove(dev);
 	return 0;
 }