lwt: fix rx checksum setting for lwt devices tunneling over ipv6

[ Upstream commit c868ee70 ]

the commit 35e2d115 ("tunnels: Allow IPv6 UDP checksums to be
correctly controlled.") changed the default xmit checksum setting
for lwt vxlan/geneve ipv6 tunnels, so that now the checksum is not
set into external UDP header.
This commit changes the rx checksum setting for both lwt vxlan/geneve
devices created by openvswitch accordingly, so that lwt over ipv6
tunnel pairs are again able to communicate with default values.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Jesse Gross <jesse@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/openvswitch/vport-vxlan.c

@@ -90,7 +90,7 @@ static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
 	int err;
 	struct vxlan_config conf = {
 		.no_share = true,
-		.flags = VXLAN_F_COLLECT_METADATA,
+		.flags = VXLAN_F_COLLECT_METADATA | VXLAN_F_UDP_ZERO_CSUM6_RX,
 	};
 
 	if (!options) {