ignore wide channel configs that do not appear in the 802.11ac spec

ignore wide channel configs that do not appear in the 802.11ac spec

Wide channel configurations not listed in operating class tables of
the 802.11ac spec can trigger regulatory assertion failures in iwm(4)
firmware, and potentially other device firmware.
Ignore non-standard channels configs such that we downgrade to 40MHz
or even 20MHz to make such APs usable, albeit at lower speed.

Found by dlg@ with a mikrotik AP advertising channel configs that do
not appear as such in the spec:
  80 MHz: |104|108|112|116|
  40 MHz: |primary: 112|secondary above: 116|
Either of these triggered iwm0: 0x000014FD | ADVANCED_SYSASSERT

Fix tested by myself on iwx(4) AX200 and dlg@ on iwm(4) 7260.
Johannes Berg helped with deciphering the error code, thanks!