selftests, bpf: Add one test for sockmap with strparser

selftests, bpf: Add one test for sockmap with strparser

[ Upstream commit d69672147faa2a7671c0779fa5b9ad99e4fca4e3 ]

Add the test to check sockmap with strparser is working well.

Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211029141216.211899-3-liujian56@huawei.com
Stable-dep-of: 523dffccbade ("selftests/bpf: Fix total_bytes in msg_loop_rx in test_sockmap")
Signed-off-by: Sasha Levin <sashal@kernel.org>