community/sensorfw: fix service init
The default config is /etc/sensorfw/sensord.conf, but we're using primaryuse.conf. Also add --no-magnetometer-bg-calibration as found in the upstream .service file.
The default config is /etc/sensorfw/sensord.conf, but we're using primaryuse.conf. Also add --no-magnetometer-bg-calibration as found in the upstream .service file.