[tz] gcc 8 demanded patch (from NetBSD)

[Robert Elz]

    Date:        Wed, 10 May 2017 16:29:15 -0700
    From:        Paul Eggert <eggert at cs.ucla.edu>
    Message-ID:  <cfe0e56a-6661-faac-4c32-f9d1435a314b at cs.ucla.edu>

  | If I've calculated things correctly, in ~1400 years [...]
  | Something will have to give.

I shall be looking forward to observing that happen...

kre