allow negative cache entries to be returned

lib/dns/view.c

@@ -427,7 +427,9 @@ dns_view_find(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type,
  cleanup:
 	if (result != ISC_R_SUCCESS &&
 	    result != DNS_R_GLUE &&
-	    result != DNS_R_HINT)
+	    result != DNS_R_HINT &&
+	    result != DNS_R_NCACHENXDOMAIN &&
+	    result != DNS_R_NCACHENXRRSET)
 		result = DNS_R_NOTFOUND;
 
 	if (zrdataset.methods != NULL) {