bpf/selftests: Add verifier tests for loading sleepable programs

Adding verifier tests for loading all types od allowed
sleepable programs plus reject for tp_btf type.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230117223705.440975-2-jolsa@kernel.org


Signed-off-by: Alexei Starovoitov <ast@kernel.org>