Bluetooth: Disconnect HIDRAW devices on disconnect

Currently the HID subsystem will create HIDRAW devices for the transport
driver, but it will not disconnect them. Until the HID subsytem gets
fixed, ensure that HIDRAW and HIDDEV devices are disconnected when the
Bluetooth HID device gets removed.

Based on a patch from Brian Rogers <brian@xyzw.org>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>