Fix an mdoc(7) macro that is not an option in the provided
description.

Bump Dd.

As CDDL License dictates, update the Copyright accordingly.

Sponsored by:	The FreeBSD Foundation


git-svn-id: svn+ssh://svn.freebsd.org/base/head@274418 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f