PnP device notifications/events are currently sent and received from the `plugplay` service as the raw-bytes for the `DBT_DEVTYP_DEVICEINTERFACE` struct that needs to be sent from the PnP code in `ntoskrnl.exe`. While simple, it does not support sending `DBT_DEVTYP_HANDLE` events, as they also include a `HANDLE` to the device the event comes from, which cannot simply be sent as raw bytes. This MR reworks how notifications are sent and received from the `plugplay` service, by:
1. Introducing new structs `DEVICE_BROADCAST_HANDLE` and `DEVICE_BROADCAST_DEVICEINTERFACE` in `plugplay.idl`. The structs are similar to their counterparts in `dbt.h` without the `devicetype` and `size` fields added for the header. 2. Re-write `plugplay_{send,get}_event` to use the newly added union `DEVICE_BROADCAST`, which uses the `devicetype` value as the discriminant. A deep copy of this union is then appended to the event queue of every registered listener. 3. Re-write `I_ScRegisterDeviceNotification` and `device_notify_proc` in `sechost/service.c` to use the newly added types instead. Additionally, add support for registering for `DBT_DEVTYPE_HANDLE` notifications, for which the `OBJECT_NAME_INFORMATION` value for the device `HANDLE` is used to filter notifications in order to correctly dispatch them to their registered callbacks. 4. Re-write the callbacks in `user32/input.c` to accept the `DEVICE_BROADCAST` union instead, and construct the appropriate `DEV_BROADCAST_*` struct from it, which gets sent to `SendMessageTimeoutW` as usual.
Support for `DBT_DEVTYP_HANDLE` is needed for the Bluetooth driver stack I have been working on recently, which uses `DBT_DEVTYP_HANDLE` events to notify userspace about newly found Bluetooth devices during discovery and incoming authentication requests, as documented by MS [here](https://learn.microsoft.com/en-us/windows/win32/bluetooth/bluetooth-and-wm-d...).
-- v27: plugplay: Broadcast PnP events on a dedicated thread.