samples/bpf: xdp_redirect_cpu_user: Do not update bpf maps in option loop

Do not update xdp_redirect_cpu maps running while option loop but
defer it after all available options have been parsed. This is a
preliminary patch to pass the program name we want to attach to the
map entries as a user option

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/95dc46286fd2c609042948e04bb7ae1f5b425538.1594734381.git.lorenzo@kernel.org