selftests/bpf: Add the traffic monitor option to test_progs.

Add option '-m' to test_progs to accept names and patterns of test cases.
This option will be used later to enable traffic monitor that capture
network packets generated by test cases.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240815053254.470944-3-thinker.li@gmail.com


Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>