selftests/bpf: remove duplicated functions
The file cgroup_tcp_skb.c contains redundant implementations of the similar
functions (create_server_sock_v6(), connect_client_server_v6() and
get_sock_port_v6()) found in network_helpers.c. Let's eliminate these
duplicated functions.
Changes from v1:
- Remove get_sock_port_v6() as well.
v1: https://lore.kernel.org/all/
20230807193840.567962-1-thinker.li@gmail.com/
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20230808162858.326871-1-thinker.li@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>