354861-354863,354865,355254,355450,355452

netinet*: variable cleanup
netinet*: update *mp to pass the proper value back
nd6 defrouter: consolidate nd_defrouter manipulations in nd6_rtr.c
  (excluding some changes to keep public KPI)
nd6: simplify code
netinet6: Remove PULLDOWN_TESTs.
netinet*: replace IP6_EXTHDR_GET()
IP6_EXTHDR_CHECK(): remove the last instances
nd6_rtr: consollidation and more consistent naming
ipv6 tests: Add a simple ping6 test as well.
icmpv6: Fix mbuf change in mld
nd6_rtr: re-sort functions
nd6: make nd6_timer_ch static
nd6: sysctl
in6: move include
Fix m_pullup() problem after removing PULLDOWN_TESTs and KAME EXT* macros.
  (IP6_EXTHDR* macros are preserved in stable).
ip6_input: remove redundant v4mapped check
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