selftests/bpf: Fix test_verif_scale{1,3} SEC() annotations

Use proper SEC("tc") for test_verif_scale{1,3} programs. It's not
a problem for selftests right now because we manually set type
programmatically, but not having correct SEC() definitions makes it
harded to generically load BPF object files.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220909193053.577111-2-andrii@kernel.org