samples/bpf: extend test_tunnel_bpf.sh with ERSPAN

Extend existing tests for vxlan, gre, geneve, ipip to
include ERSPAN tunnel.

Signed-off-by: William Tu <u9012063@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>