performed, so that with nonzero target-fetch-policy it fetches
forwarder addresses and uses them from cache. Also updated that
delegation point cache fill routines use CDflag for AAAA message
lookups, so that its negative lookup stops a recursion since the
cache uses the bit for disambiguation for dns64 but the recursion
uses CDflag for the AAAA target lookups, so the check correctly
stops a useless recursion by its cache lookup.
