resolved: always return the validated answers when validating

resolved: always return the validated answers when validating

We normally expect sd-resolved only to return the validated subset of a
validated response. In some cases we give up on validating, because we
have enough information already to conclude the answer is bogus.

Let's be sure to always reply with only the validated subset in these
cases too, so that we don't return bogus answers and confuse primitive
clients that won't see the SERVFAIL rcode.