x/pkgsite: missing urls for some licenses

What is the URL of the page with the issue?

https://pkg.go.dev/license-policy

What did you expect to see?

all of the license should point to url that describe the license.

What did you see instead?

but some of them don't

[sudo-sturbia]

@julieqiu I would like to claim this if it's possible. If so, do you have a preference for the remaining links, for example spdx.org/licenses? Thanks!

[gopherbot]

Change https://golang.org/cl/257837 mentions this issue: internal/licenses: provide links for non-OSI licenses