ixgbe: code refactoring
ixgbe: code refactoring

   - ixgbe_rx_alloc_bufs():
      - Reset the rte_mbuf fields only when requested.
      - Take the RDT update out of the function.
      - Add the stub when RTE_LIBRTE_IXGBE_RX_ALLOW_BULK_ALLOC is not defined.
   - ixgbe_recv_scattered_pkts():
      - Take the code that updates the fields of the cluster's HEAD buffer into
        the inline function.

Signed-off-by: Vlad Zolotarov <976c0f8d0852ed6439ad273880b400a75a7c41d0@cloudius-systems.com>
Acked-by: Konstantin Ananyev <cbd5212b59ab42a210d72992d23a3aa17cfd3eaf@intel.com>

mixja/dpdk,venkynv/dpdk-mirror,msune/dpdk,tsphillips/dpdk-fork,venkynv/dpdk-mirror,msune/dpdk,msune/dpdk,msune/dpdk,john-mcnamara-intel/dpdk,tsphillips/dpdk-fork,mixja/dpdk,john-mcnamara-intel/dpdk,tsphillips/dpdk-fork,tsphillips/dpdk-fork,mixja/dpdk,venkynv/dpdk-mirror,mixja/dpdk,john-mcnamara-intel/dpdk,venkynv/dpdk-mirror,john-mcnamara-intel/dpdk