Ask IANA to update registration information
Per rfc8126 section 8 we should request that the registry information is updated to the new RFC. It should be enough to add a note like:
Because this document obsoletes RFC 4637, IANA is asked to change
all registration information that references [RFC4637] to instead
reference [[this RFC]].
It's not clear how we should approach the existing "This specification creates a registry" part. See ml post.
Edited by Ángel González