selftests/bpf: Add missing section name tests for getpeername/getsockname

These were missed when these hooks were first added so add them now
instead to make sure every sockaddr hook has a matching section name
test.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-2-daan.j.demeyer@gmail.com


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