wpa_supplicant error for iwn0

[Ron Georgia <netverbs%gmail.com@localhost>]

All,
I am getting an error with wpa_supplicant.

Starting wpa_supplicant.
Successfully initialized wpa_supplicant
ioctl[SIOCS80211, op=20, val=0, arg_len=7]: Invalid argument
ioctl[SIOCS80211, op=20, val=0, arg_len=7]: Invalid argument

From dmesg:
$ dmesg | grep -i -E 'iwn|firmware|80211'                            [19:13:04]
[     1.047447] iwn0 at pci2 dev 0 function 0: Intel Centrino Advanced-N 6235 (rev. 0x24)
[     1.047447] iwn0: interrupting at msi2 vec 0
[     1.047447] iwn0: MIMO 2T2R, AGN, address c8:f7:33:8a:bf:c9
[     1.053458] iwn0 at pci2 dev 0 function 0: Intel Centrino Advanced-N 6235 (rev. 0x24)
[     1.053458] iwn0: interrupting at msi2 vec 0
[     1.053458] iwn0: MIMO 2T2R, AGN, address c8:f7:33:8a:bf:c9
[     1.052706] iwn0 at pci2 dev 0 function 0: Intel Centrino Advanced-N 6235 (rev. 0x24)
[     1.052706] iwn0: interrupting at msi2 vec 0
[     1.052706] iwn0: MIMO 2T2R, AGN, address c8:f7:33:8a:bf:c9

I am using a nuc 
CPU: Intel(R) Core(TM) i3-3217U (4) @ 1.80 GHz
GPU 1: Intel Device 0166 (VGA compatible)
GPU 2: Intel Mesa DRI Intel(R) HD Graphics 4000 (IVB GT2)

I am running OS: NetBSD 11.99.7 amd64, Kernel: NetBSD 11.99.7
My /etc/wpa_supplicant.conf is "barebones" with only ssid and psk. And
of course:
ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=wheel

My /etc/rc.conf entry for network is:
ifconfig_iwn0="up"
wpa_supplicant=YES
wpa_supplicant_flags="-i iwn0 -c /etc/wpa_supplicant.conf"
dhcpcd=YES
dhcpcd_flags="-qM wm0 iwn0"

I booted from a NetBSD 11.0 kernel and got the same result. 

Any suggestions? Do I need /etc/ifconfig.iwn0?