regulator: mt6358: Add output voltage fine tuning to fixed regulators

The "fixed" LDO regulators found on the MT6358 and MT6366 PMICs have
either no voltage selection register, or only one valid setting.
However these do have a fine voltage calibration setting that can
slightly boost the output voltage from 0 mV to 100 mV, in 10 mV
increments.

Add support for this by changing these into linear range regulators.
Some register definitions that are missing are also added.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230913082919.1631287-3-wenst@chromium.org


Signed-off-by: Mark Brown <broonie@kernel.org>