Symmetric RSS in DPDK for 82599

#define RSS_HASH_KEY_LENGTH 40
static uint8_t hash_key[RSS_HASH_KEY_LENGTH] = {
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
};

struct rte_eth_conf port_conf = {
  .rxmode = {
    .mq_mode = ETH_MQ_RX_RSS,
  },
  .rx_adv_conf = {
    .rss_conf = {
        .rss_key = hash_key,
        .rss_key_len = RSS_HASH_KEY_LENGTH,
        .rss_hf = ETH_RSS_IP |
              ETH_RSS_TCP |
              ETH_RSS_UDP |
              ETH_RSS_SCTP,
    }
   },
};

rte_eth_dev_configure(port_id, rx_queue_num, tx_queue_num, &port_conf);