In OpenFlow Spec 1.3.4, ipv6_exthdr is maskable match field,
but ofctl_v1_3 does not support mask.
This patch makes ofctl_v1_3 enable to set masked ipv6_exthdr.
Signed-off-by: IWASE Yusuke <iwase.yusuke0@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>