kunit: unregister the device on error

kunit_init_device() should unregister the device on bus register error,
but mistakenly it tries to unregister the bus.

Unregister the device instead of the bus.
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Fixes: d03c720e ("kunit: Add APIs for managing devices")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/kunit/device.c

@@ -51,7 +51,7 @@ int kunit_bus_init(void)
 
 	error = bus_register(&kunit_bus_type);
 	if (error)
-		bus_unregister(&kunit_bus_type);
+		root_device_unregister(kunit_bus_device);
 	return error;
 }