[FS#1133] Can't set channels 12 and 13 on Raspberry Pi 3 in AP config

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Waldemar Konik (valdi74) 

Attached to Project - LEDE Project
Summary - Can't set channels 12 and 13 on Raspberry Pi 3 in AP config
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Średnia
Priority - Normalny
Reported Version - All
Due in Version - Undecided
Due Date - Undecided
Details - It is not possible to set up channel 12/13 on Raspberry Pi 3 in Wifi AP configuration. I get error "brcmfmac: brcmf_cfg80211_start_ap: Set Channel failed: chspec=4109, -20".
Tested on 17.01.1 and latest snapshot (r5217-098afa1).
PS Raspbian works properly on 13 channel as AP.

Logs:
root at LEDE:~# uci show wireless
wireless.radio0=wifi-device
wireless.radio0.type='mac80211'
wireless.radio0.hwmode='11g'
wireless.radio0.path='platform/soc/3f300000.mmc/mmc_host/mmc1/mmc1:0001/mmc1:0001:1'
wireless.radio0.htmode='HT20'
wireless.radio0.disabled='0'
wireless.radio0.country='PL'
wireless.radio0.channel='11'
wireless.default_radio0=wifi-iface
wireless.default_radio0.device='radio0'
wireless.default_radio0.network='lan'
wireless.default_radio0.mode='ap'
wireless.default_radio0.ssid='Dantooine'
wireless.default_radio0.encryption='psk2'
wireless.default_radio0.key='secret'

root at LEDE:~# wifi
[  828.291269] device wlan0 left promiscuous mode
[  828.301579] br-lan: port 2(wlan0) entered disabled state
[  830.594037] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[  830.608333] br-lan: port 2(wlan0) entered blocking state
[  830.619697] br-lan: port 2(wlan0) entered disabled state
[  830.631336] device wlan0 entered promiscuous mode
[  830.911507] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[  830.924197] br-lan: port 2(wlan0) entered blocking state
[  830.935606] br-lan: port 2(wlan0) entered forwarding state

root at LEDE:~# uci set wireless.radio0.channel=13
root at LEDE:~# uci commit wireless
root at LEDE:~# wifi
[  913.551274] device wlan0 left promiscuous mode
[  913.561751] br-lan: port 2(wlan0) entered disabled state
[  915.854693] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[  915.869110] br-lan: port 2(wlan0) entered blocking state
[  915.880481] br-lan: port 2(wlan0) entered disabled state
[  915.892046] device wlan0 entered promiscuous mode
[  916.080443] brcmfmac: brcmf_cfg80211_start_ap: Set Channel failed: chspec=4109, -20
[  916.131249] device wlan0 left promiscuous mode
[  916.142014] br-lan: port 2(wlan0) entered disabled state
[  927.997654] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[  928.012458] br-lan: port 2(wlan0) entered blocking state
[  928.024440] br-lan: port 2(wlan0) entered disabled state
[  928.036703] device wlan0 entered promiscuous mode
[  928.222287] brcmfmac: brcmf_cfg80211_start_ap: Set Channel failed: chspec=4109, -20
[  928.301237] device wlan0 left promiscuous mode
[  928.312608] br-lan: port 2(wlan0) entered disabled state

root at LEDE:~# uci set wireless.radio0.channel=11
root at LEDE:~# uci commit wireless
root at LEDE:~# wifi
[  990.032785] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[  990.048153] br-lan: port 2(wlan0) entered blocking state
[  990.060246] br-lan: port 2(wlan0) entered disabled state
[  990.072619] device wlan0 entered promiscuous mode
[  990.351670] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[  990.365070] br-lan: port 2(wlan0) entered blocking state
[  990.377132] br-lan: port 2(wlan0) entered forwarding state
[ 1000.491313] device wlan0 left promiscuous mode
[ 1000.502769] br-lan: port 2(wlan0) entered disabled state
[ 1002.676007] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[ 1002.691453] br-lan: port 2(wlan0) entered blocking state
[ 1002.703651] br-lan: port 2(wlan0) entered disabled state
[ 1002.716135] device wlan0 entered promiscuous mode
[ 1003.093512] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 1003.107183] br-lan: port 2(wlan0) entered blocking state
[ 1003.119522] br-lan: port 2(wlan0) entered forwarding state

root at LEDE:~# iw list
Wiphy phy0
	max # scan SSIDs: 10
	max scan IEs length: 2048 bytes
	max # sched scan SSIDs: 16
	max # match sets: 16
	max # scan plans: 1
	max scan plan interval: 508
	max scan plan iterations: 0
	Retry short limit: 7
	Retry long limit: 4
	Coverage class: 0 (up to 0m)
	Device supports T-DLS.
	Available Antennas: TX 0 RX 0
	Supported interface modes:
		 * IBSS
		 * managed
		 * AP
		 * P2P-client
		 * P2P-GO
		 * P2P-device
	Band 1:
		Capabilities: 0x1020
			HT20
			Static SM Power Save
			RX HT20 SGI
			No RX STBC
			Max AMSDU length: 3839 bytes
			DSSS/CCK HT40
		Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
		Minimum RX AMPDU time spacing: 16 usec (0x07)
		HT TX/RX MCS rate indexes supported: 0-7
		Frequencies:
			* 2412 MHz [1] (20.0 dBm)
			* 2417 MHz [2] (20.0 dBm)
			* 2422 MHz [3] (20.0 dBm)
			* 2427 MHz [4] (20.0 dBm)
			* 2432 MHz [5] (20.0 dBm)
			* 2437 MHz [6] (20.0 dBm)
			* 2442 MHz [7] (20.0 dBm)
			* 2447 MHz [8] (20.0 dBm)
			* 2452 MHz [9] (20.0 dBm)
			* 2457 MHz [10] (20.0 dBm)
			* 2462 MHz [11] (20.0 dBm)
			* 2467 MHz [12] (20.0 dBm)
			* 2472 MHz [13] (20.0 dBm)****
			* 2484 MHz [14] (disabled)
	valid interface combinations:
		 * #{ managed }