bpf, samples: Remove AF_XDP samples

bpf, samples: Remove AF_XDP samples

Remove the AF_XDP samples from samples/bpf/ as they are dependent on
the AF_XDP support in libbpf. This support has now been removed in the
1.0 release, so these samples cannot be compiled anymore. Please start
to use libxdp instead. It is backwards compatible with the AF_XDP
support that was offered in libbpf. New samples can be found in the
various xdp-project repositories connected to libxdp and by googling.

Signed-off-by: Magnus Karlsson <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Maciej Fijalkowski <[email protected]>
Acked-by: Jesper Dangaard Brouer <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]