SDRAngel crashes on PATCH /sdrangel/deviceset/{deviceSetIndex}/channel/{channelIndex}/settings with FreqScannerSettings.

[zuker]

STR:

1. Create deviceset with any device, add Frequency Scanner with UI
2. Run

curl -X PATCH "http://localhost:8091/sdrangel/deviceset/0/channel/0/settings" -H  "accept: application/json" -H  "Content-Type: application/json" -d "{  \"FreqScannerSettings\": {    \"channelBandwidth\": 25000,    \"channelFrequencyOffset\": 25000,    \"channelMarker\": {      \"centerFrequency\": 0,      \"color\": -16724536,      \"frequencyScaleDisplayType\": 0,      \"title\": \"Frequency Scanner\"    },    \"frequencies\": [      {        \"enabled\": 1,        \"frequency\": 100000000      }    ],    \"reverseAPIAddress\": \"127.0.0.1\",    \"reverseAPIChannelIndex\": 0,    \"reverseAPIDeviceIndex\": 0,    \"reverseAPIPort\": 8888,    \"rgbColor\": -16724536,    \"rollupState\": {      \"childrenStates\": [        {          \"isHidden\": 0,          \"objectName\": \"settingsContainer\"        }      ],      \"version\": 0    },    \"streamIndex\": 0,    \"threshold\": -60,    \"title\": \"Frequency Scanner\",    \"useReverseAPI\": 0  },  \"channelType\": \"FreqScanner\",  \"direction\": 0}"

ER: Frequemcy Scanner configured
AR: app crashes

[f4exb]

PR actually fixes the bug