linux-phytec-ti

bpf: test_sockmap, add options for msg_pop_data() helper

Similar to msg_pull_data and msg_push_data add a set of options to
have msg_pop_data() exercised.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>