Kernel commit 04fd61ab36ec ("bpf: allow bpf programs to tail-call other
bpf programs") added support for tail calls, this patch here adds tc
front end parts for the object parser to prepopulate a given eBPF prog
array before the root prog is pushed down for classifier creation. The
prepopulation works with any number of prog arrays in any dependencies,
e.g. prog or normal maps could also be used from progs that are
tail-called themself, etc.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>