Remove dead code

Remove dead code

    *** CID 352812:  Control flow issues  (DEADCODE) /lib/ns/query.c: 8584 in query_filter64()
    8578     cleanup:
    8579     	if (buffer != NULL) {
    8580     		isc_buffer_free(&buffer);
    8581     	}
    8582
    8583     	if (myrdata != NULL) {
    >>>     CID 352812:  Control flow issues  (DEADCODE)
    >>>     Execution cannot reach this statement: "dns_message_puttemprdata(cl...".
    8584     		dns_message_puttemprdata(client->message, &myrdata);
    8585     	}
    8586
    8587     	if (myrdataset != NULL) {
    8588     		dns_message_puttemprdataset(client->message, &myrdataset);
    8589     	}