In addition to device removed status monitoring in gst_d3d11_result()
method, if ID3D11Device4 interface is available,
an event handle will be used for device removed status update.
And "device-removed" signal is removed since applications can monitor
the device removed status via gobject notify
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6699>