selftests/bpf: add "any alignment" annotation for some tests

RISC-V does, in-general, not have "efficient unaligned access". When
testing the RISC-V BPF JIT, some selftests failed in the verification
due to misaligned access. Annotate these tests with the
F_NEEDS_EFFICIENT_UNALIGNED_ACCESS flag.

Signed-off-by: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>