bq27x00_battery: Report -ENODATA if bq27000 battery was not calibrated

* CI (Capacity Inaccurate) flag is set after full reset on bq27000 battery
* when is set, all capacity properties should be reported incorrectly,
  because there was no learning cycle and battery was not calibrated
* instead reporting incorrect values, report -ENODATA

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>