Fix in packet_parse_rest()

- It does not try to parse anything if the whole packet is already
  parsed.

libknot/packet/packet.c

@@ -825,6 +825,10 @@ int knot_packet_parse_rest(knot_packet_t *packet)
 //		return KNOT_EOK;
 //	}
 
+	if (packet->parsed == packet->size) {
+		return KNOT_EOK;
+	}
+	
 	size_t pos = packet->parsed;
 
 	return knot_packet_parse_rr_sections(packet, &pos);