test: bpf: add a testcase reduced from nmap

test: bpf: add a testcase reduced from nmap

nmap generates classic BPF programs to filter ARP packets with given target MAC
which triggered a bug in eBPF x64 JIT. The bug was fixed in
commit e0ee9c12157d ("x86: bpf_jit: fix two bugs in eBPF JIT compiler")
This patch is adding a testcase in eBPF instructions (those that
were generated by classic->eBPF converter) to be processed by JIT.
The test is primarily targeting JIT compiler.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>