hotplug DEVICE won't be reported on ifdown

OpenWrt 25.12.0-rc1.

```
~ # ifdown wan2
~ # Wed Jan  7 07:14:13 2026 user.notice hotplug: ifdown wan2

~ # ifup wan2
~ # Wed Jan  7 07:14:42 2026 user.notice hotplug: ifup wan2 lan1
```

`/etc/hotplug.d/iface/99-test`

```
#!/bin/sh

logger -t hotplug "$ACTION $INTERFACE $DEVICE"
```