selftests/bpf: enable tracing_struct tests for arm64

Now that the constraint preventing attachment to functions consuming
struct on stack has been removed from the kernel (and moved to pahole,
with a slightly smarter detection, to prevent only those that are
packed), re-enable the tracing_struct tests for arm64.

Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com>
Link: https://lore.kernel.org/r/20250709-arm64_relax_jit_comp-v1-2-3850fe189092@bootlin.com


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