Add config used for benchmark results

Commit the config used for XDP-project benchmark:
 areas/arm64/board_espressobin08_bench_xdp.org

Link:
 https://github.com/xdp-project/xdp-project/blob/master/areas/arm64/board_espressobin08_bench_xdp.org

This will make it easier to reproduce and identify
performance differences that can be related to kernel
config options.