ccdconfig: Update licensing terms.

The code originate in NetBSD and there are the copyright notes have been
assigned to the NetBSD Foundation. Update the files up to the point where
we started diverging.

Further relaxation of the licensing terms are possible after we
check the NetBSD updates, and contact the local authors.

In the case of ccdconfig.8 this reinstates the 3rd clause but since the
code is not directly from Berkeley, the change was bogus.

Obtained from: NetBSD