MFC r263812:

  Update build(7) with LOCAL_* vars
o Provide a compatibility shim for netstat(1) to obtain output queue
  drops via NET_RT_IFLISTL sysctl. The sysctl handler appends oqdrops
  at the end of struct if_msghdrl, and netstat(1) sees that as an
  additional field of struct if_data. This allows us to fetch the data
  keeping ABI and API compatibility.
  This is direct commit to stable/10.

o Merge r263331 from head, to restore printing of queue drops.

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