Extend existing tests for vxlan, gre, geneve, ipip, erspan,
to include ip6 gre and gretap tunnel.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>