Change status on offline device.
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### What issue do you have? Please be as thorough and explicit as possible.



### Details of your setup.
* Do you use (1) Homebridge (+ config-ui), (2) Homebridge (CLI) or (3) HOOBS? 
1


* Which version of Homebridge/HOOBS do you have?
homebridge-config-ui-x v4.41.0


* Which platform do you run Homebridge/HOOBS on (e.g. Raspberry Pi/Windows/HOOBS Box)? Please also mention your version of Node.js/NPM if known.
Raspberry


* Which version of this plugin (homebridge-ewelink) do you have? Has the issue started since upgrading from a previous version?
homebridge-ewelink v5.6.0


* Which eWeLink devices do you have that are causing issues? Please include product models if applicable.



### Please paste any relevant logs below.
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```

```
When I click on an offline device in homebridge, it changes state even though the log in prints that the device is offline.
It would be a good idea not to show as if you had managed to turn the device on or off.
![before](https://user-images.githubusercontent.com/10674642/112755218-08527500-8fe0-11eb-971a-f4359f2344c9.png)
![after](https://user-images.githubusercontent.com/10674642/112755226-0c7e9280-8fe0-11eb-8f3d-9fa318d2831f.png)
![log](https://user-images.githubusercontent.com/10674642/112755234-17d1be00-8fe0-11eb-9c16-b1f7c1189601.png)


