- Add IPv6 outbound packet counter. - Fix bug of comparison that size of packet exceeds mtu.
- Add IPv6 outbound packet counter.
- Fix bug of comparison that size of packet exceeds mtu.

MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame