power: rk8xx: properly print all supported PMICs name

The ID of the PMIC is stored in the 2 16b registers but the only part
that matters right now is the 3 MSB, which make the 3 digits (in hex) of
the part number.

Right now, only RK808 was properly displayed, with this all currently
supported PMICs should display the proper part number.

Additionally, when the PMIC variant is not found, print that value
instead of the masked unshifted value as all PMICs we support for now
have their LSB ignored to represent the actual part number.

Tested on RK806 (RK3588 Jaguar), RK808 (RK3399 Puma) and RK809 (PX30
Ringneck).

Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Quentin Schulz <quentin.schulz@cherry.de>