Public domain dedication

The component this notice accompanies carries no licence terms because its author released it into the
public domain. There is no copyright to attribute, no notice to reproduce and no condition attached to
using, copying, modifying or redistributing it, in source or in binary form.

`LicenseRef-public-domain` is not an SPDX licence identifier. It is the SPDX-conformant way of naming a
licensing situation that has no identifier: a bare public-domain dedication with no accompanying licence
text of its own. The entry in `THIRD-PARTY.md` that points here names the component, its upstream project
and the wording its own source files carry.

No warranty of any kind is offered by the authors of such a component, nor by anyone redistributing it.
