sensor: bq274xx: add support for bq27427

The current ID for BQ274XX_DEVICE_ID is actually the one for the
BQ27421. The driver seems to work with the BQ27427 as well, at least the
common and extended commands are the same, so add that variant as well,
rename the existing one and print the currently read ID when the ID
check fails.

The configuration registers have a different offset though, so add a
register offset table and make the device rcognize the right one un
runtime based on the device ID.

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>