WLAN is not connecting after reboot when channel 12 or 13 are used
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**Describe The Bug:**
<!-- A clear and concise description of what the bug is. -->
After a reboot no WLAN connection is established if channel 12 or 13 is used.

WLAN country is set to Germany (de).
Channels 12 and 13 are generally "visible" to the raspberry.
```
pi@homebridge-garage:~ $ iwlist wlan0 channel
wlan0     13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Current Frequency:2.457 GHz (Channel 10)
```

If the WLAN router is set to channel 13, the Rapberry notices this and switches to channel 13.
```
pi@homebridge-garage:~ $ iwlist wlan0 channel
wlan0     13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Current Frequency:2.472 GHz (Channel 13)
```

If then a reboot is made, no WLAN connection will be established.

The following things I tried to solve the issue but without any effect. 
- waiting 5-10 minutes and check if the connection got established.
- add line ```country=de```to ```/etc/wpa_supplicant/wpa_supplicant.conf``` even I'm not sure if this config is used at all
- modify the file ```/etc/systemd/system/dbus-fi.w1.wpa_supplicant1.service```and change the line ```Before=network.target``` to ```Before=network.target NetworkManager.service```, again not knowing if spa_supplicant.conf is used at all. The idea was to make sure the WLAN country is set to ```de``` before the NetworkManager starts to connect to the WLAN.
- use nmtui to remove the connection "Homebridge WiFi Setup" to check if that has any impact. This connection came back after reboot.

**To Reproduce:**
<!-- Steps to reproduce the behavior. -->

- Set channel at WLAN router to a channel < 11.
- Start raspberry
- WLAN connection is established
- Change channel at WLAN router to 12 or 13
- do reboot
- No WLAN connection is established

**Expected behavior:**
<!-- A clear and concise description of what you expected to happen. -->
- A WLAN connection should establish even using channel 12 or 13

**Logs:**

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**Screenshots:**
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**Environment:**

* **Homebridge Raspberry Pi Image Version**: Homebridge Raspbian v1.0.14 - Raspberry Pi Zero W Rev 1.1 
* **Node.js Version**: v14.15.0
* **NPM Version**: v6.14.8
* **Homebridge Version**: v1.1.6
* **Homebridge Config UI X Plugin Version**: v4.31.0

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