rte_eth_bond_8023ad_slave_info() wasn't exported in the original work.
Useful to extract information about the current 802.3ad state.
Fixes: 46fb43683679 ("bond: add mode 4")
Cc: stable@dpdk.org
Signed-off-by: Chas Williams <chas3@att.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>