probable error in 66.html regarding rpki-client

[Ross L Richardson]

66.html claims that rpki-client is included, but:
- <https://man.openbsd.org/rpki-client.8> gives no result.
- The test system I just sysupgraded doesn't have it.

It's not actually linked to the build (in src/usr.sbin/Makefile), is it?

Ross