No errors in homebridge, but no accessories added
<!-- Provide a general summary in the Title above -->
Just configured the plugin, it seems to connect, but no HS110 appears neither in homebridge accessories web UI nor in iOS Home app. 

### Expected Behavior
<!-- If you're describing a bug, tell us what should happen -->
<!-- If you're suggesting a change/improvement, tell us how it should work -->
Accessories, in my case 2 HS110 plugs should appear in homebridge/home app

### Current Behavior
<!-- If describing a bug, tell us what happens instead of the expected behavior -->
<!-- If suggesting a change/improvement, explain the difference from current behavior -->
Accessories doesn't appear.

### Steps to Reproduce (for bugs)
<!-- Please add a series of steps to reproduce the problem. -->
Only configured plugin with the basic configuration and the problem appears.

### Versions
<!-- Please run commands and include versions below. -->
- **Node**:       `node --version`
- **Homebridge**: `homebridge --version`
- **OS**:         <!-- The version and architecture of your operating system -->
/homebridge # node --version
v14.15.0
/homebridge # homebridge --version
1.2.3
/homebridge # uname -a
Linux e375beaaac83 4.14.24-qnap #1 SMP Sat Oct 24 01:14:15 CST 2020 x86_64 GNU/Linux
/homebridge #
Running within the oznu/homebridge:latest docker image.

### Configuration
<!-- Please include the TplinkSmarthome platform section of your config.json file.
Paste between the the two ``` lines below.
-->
```json
{
            "name": "TplinkSmarthome",
            "platform": "TplinkSmarthome"
}
```

### Homebridge Log / Command Output
<!-- Paste relevant output between the two ``` lines below
  - Remove any sensitive information, passwords, etc.
  - If output is long:
    - Please extract only the relevant portions if possible (remove other plugin's output, etc)
    - Consider creating a gist, etc
  - However, please include the beginning of the log where the homebridge initialization happens if possible
-->
```
[11/2/2020, 9:40:36 PM] [TplinkSmarthome] Initializing TplinkSmarthome platform...
[11/2/2020, 9:40:36 PM] [TplinkSmarthome] homebridge-tplink-smarthome v6.1.0, node v14.15.0, homebridge v1.2.3
[11/2/2020, 9:40:36 PM] Loading 2 accessories...
```
