drivers: dio: fix possible memory leak in dio_init()

If device_register() returns error, the 'dev' and name needs be
freed. Add a release function, and then call put_device() in the
error path, so the name is freed in kobject_cleanup() and to the
'dev' is freed in release function.

Fixes: 2e4c77bea3d8 ("m68k: dio - Kill warn_unused_result warnings")
Fixes: 1fa5ae857bb1 ("driver core: get rid of struct device's bus_id string array")
Signed-off-by: Yang Yingliang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/dio/dio.c

···
 
 #endif /* CONFIG_DIO_CONSTANTS */
 
+static void dio_dev_release(struct device *dev)
+{
+	struct dio_dev *ddev = container_of(dev, typeof(struct dio_dev), dev);
+	kfree(ddev);
+}
+
 int __init dio_find(int deviceid)
 {
 	/* Called to find a DIO device before the full bus scan has run.
···
 		dev->bus = &dio_bus;
 		dev->dev.parent = &dio_bus.dev;
 		dev->dev.bus = &dio_bus_type;
+		dev->dev.release = dio_dev_release;
 		dev->scode = scode;
 		dev->resource.start = pa;
 		dev->resource.end = pa + DIO_SIZE(scode, va);
···
 		if (error) {
 			pr_err("DIO: Error registering device %s\n",
 			       dev->name);
+			put_device(&dev->dev);
 			continue;
 		}
 		error = dio_create_sysfs_dev_files(dev);