No wifi (iwn) after main-n278149-6b96e7a57317 -> main-n278156-b2ac169802eb

TL;DR: Wireless NIC iwn was working on my main laptop with
main-n278149-6b96e7a57317; after updating (this morning) to
main-n278156-b2ac169802eb, it did not.

Some additional details:
* For the last few weeks, I have only tested this at home (daily
  updates/tracking head); this morning, the rebuild itself was done at
  home, but by the time for the reboot after the update, I was on my way
  to the office,  so I was on a commuter train (with WiFi that uses a
  captive portal).
* The "wifi" LEP on the laptop, which normally is on when the wiwif NIC
  is enabled, was not on.  I tried issung "service netif restart wlan0";
  the wifi LED flickered briefly, then went out.
* I rebooted to stable/14 (stable/14-n271780-0ee191f2f035) while still
  on the same train, and was able to see the wifi NIC working.
* The same laptop is presently running stable/14
  (stable/14-n271780-0ee191f2f035), using wifi, in the office.  It had
  also successfully used the wifi NIC under stable/14-n271780-0ee191f2f035
  at home.
* A different laptop (that I use for travel when I expect to need to
  cross a country's border), and which normally uses its wired NIC (em0)
  when it is at home came up under main-n278156-b2ac169802eb and
  had no issues with the wored NIC.  (It's at home right now; I
  can't readily flip the BIOS switch to tell it to activate the
  wireless NIC from here.)

I note that main-n278156-b2ac169802eb is just a couple of commits beyond
the current "stabweek" point, so that may be something of which to be
aware.

Peace,
david
-- 
David H. Wolfskill                              david@catwhisker.org
“We will measure our success not only by the battles we win, but also by
the wars that we end, and perhaps most importantly, the wars we never
get into."

See https://www.catwhisker.org/~david/publickey.gpg for my public key.