power: supply: max17040: adjust thermal channel scaling

IIO thermal channel is in millidegree while power supply framework expects
decidegree values. Adjust scaling to get correct readings.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Link: https://lore.kernel.org/r/20250430060239.12085-2-clamor95@gmail.com


Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>