ixgbe: migrate flow director filtering to new API

ixgbe: migrate flow director filtering to new API

This patch changes the add/delete/update operations to be implemented through
filter_ctrl API and RTE_ETH_FILTER_ADD/RTE_ETH_FILTER_DELETE/RTE_ETH_FILTER_UPDATE ops.
It also removes the callback functions:
 - ixgbe_eth_dev_ops.fdir_add_signature_filter
 - ixgbe_eth_dev_ops.fdir_update_signature_filter
 - ixgbe_eth_dev_ops.fdir_remove_signature_filter
 - ixgbe_eth_dev_ops.fdir_add_perfect_filter
 - ixgbe_eth_dev_ops.fdir_update_perfect_filter
 - ixgbe_eth_dev_ops.fdir_remove_perfect_filter

Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
Acked-by: Helin Zhang <helin.zhang@intel.com>