Properties that are marked constructor only aren't required to be freed before g_value_dup_string() as they can only be called once during construction. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8648>
Detected by ASan. As a drive-by fix, use free() instead of g_free() in gstalsadeviceprovider. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8619>