power: supply: max17040: Correct voltage reading

[ Upstream commit 0383024f811aa469df258039807810fc3793a105 ]

According to the datasheet available at (1), the bottom four
bits are always zero and the actual voltage is 1.25x this value
in mV.  Since the kernel API specifies that voltages should be in
uV, it should report 1250x the shifted value.

1) https://datasheets.maximintegrated.com/en/ds/MAX17040-MAX17041.pdf



Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>