d4976e0ebe
As the query_prefetch() or query_rpzfetch() could be called during "regular" fetch, we need to introduce separate storage for attaching the nmhandle during prefetching the records. The query_prefetch() and query_rpzfetch() are guarded for re-entrance by .query.prefetch member of ns_client_t, so we can reuse the same .prefetchhandle for both.