tools: bpftool: fix return value when all eBPF programs have been shown
Change the program to have a more consistent return code. Specifically,
do not make bpftool return an error code simply because it reaches the
end of the list of the eBPF programs to show.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>