[OpenAFS] On contributor agreements

[Derrick Brashear]

> I can also see the Patent License grant in the paragraph after that being
> problematic.
>
> Why do we need a contributor agreement that goes beyond saying that the
> contributor is legally permitted to provide the contribution under the
> chosen license?

I think we need an assertion that code is free of known patent
encumberance, or, if encumberance is known, a grant of patent license,
before we can accept given code.