BLE temperature sensor is missing icon on sensor card

[manuelzomer]

Describe the bug
The temperature sensor of the BLE Sense doesn't display any icon in its sensor card, it is the only sensor to do so.

To Reproduce
Steps to reproduce the behavior:

1. Connect BLE Sense
2. Select the temperature sensor
3. See missing icon on the sensor card

Expected behavior
The temperature sensor should display an icon on the sensor card like all other sensors.

Screenshots

[sebromero]

Fixed in e187447