No wlan0 interface created for an Intel(R) Centrino(R) Wireless-N 2200 BGN device

[Bertrand Petit]

	I am experiencing difficulties with an Intel wifi module installed in
a second-hand X230 Lenovo laptop and may need your help to make it work. I'm
using 11.2-STABLE (revison 339256), wlan-related modules are linked in kernel,
I flashed the latest Lenovo firmware, the device is enabled in the BIOS,
hardware switch is on the "on" position, and the antena led is lighted.

Identification:

# lspci -nn | grep Centri
03:00.0 Network controller [0280]: Intel Corporation Centrino Wireless-N 2200 [8086:0891] (rev c4)

Loading the iwn module yields:

# kldload /boot/kernel/iwn*fw.ko
# kldload if_iwn
# dmesg | grep Centri
iwn0: <Intel(R) Centrino(R) Wireless-N 2200 BGN> mem 0xf1c00000-0xf1c01fff irq 17 at device 0.0 on pci2
# sysctl net.wlan.devices
net.wlan.devices: iwn0

At that point all looks good, however the expected clonable wlan0 network
interface is not created:

# ifconfig | grep flags
em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
vboxnet0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500

	Is this device actually supported? If it is, what could be the
curlpit? If it is not, could you recommend a replacement supported PCIe
module?

-- 
%!PS -- Bertrand Petit
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