Draft: gnss: make sure the initial source list isn't empty
When uploading assistance data, we:
- save the initial source list
- disable the GNSS
- upload data
- finally re-enable the GNSS
This last step, however, depends on the saved sources list, which is by default empty as nothing initializes it. This results in the GNSS never being actually enabled:
eg25-manager
output:
** Message: 20:07:53.773: GNSS assistance data upload finished
** Message: 20:07:53.773: GNSS assistance upload step (7/9): re-enabling GNSS through ModemManager
** Message: 20:07:53.798: GNSS assistance upload step (8/9): re-enabling GNSS through AT+QGPS
** Message: 20:07:53.799: GNSS assistance upload step (9/9): finished
mmcli -m any --location-status
output:
--------------------------------
Location | capabilities: 3gpp-lac-ci, gps-raw, gps-nmea, gps-unmanaged, agps-msa,
| agps-msb
| enabled: 3gpp-lac-ci
| signals: no
--------------------------------
Marking as draft as it doesn't work properly yet.