regulator: dt-bindings: Convert active-semi PMIC docs to YAML schemas

Create YAML bindings for the Active-semi PMICs and remove the old text
files.

The bindings aren't perfect, for instance I couldn't find good
descriptions for the vendor properties in the "charger" node of the
ACT8945A because I am not familiar with the hardware and these
properties were not documented anywhere.

The YAML schemas are a bit different than what is described in the old
text files, because these were sometimes wrong or had missing
information. This is the case for the ACT8600 documentation, which
specified the valid node names for the regulators, while the driver was
expecting different names. This led to the current situation where we
have two different boards using different names for the regulators:
- arch/mips/boot/dts/ingenic/ci20.dts uses the names documented in the
  text file,
- arch/mips/boot/dts/ingenic/gcw0.dts uses the names that the driver
  expects.
In theory, the driver should be fixed to follow the documentation, and
accept both naming schemes. In practice though, when the PMIC node was
added to the ci20.dts board file, the names were already wrong in
regards to what the driver expected, so it never really worked
correctly and wasn't tested properly. Furthermore, in that board the
consumers of the regulators aren't working for various other reasons
(invalid GPIOs, etc.).

For that reason, for the ACT8600 bindings I decided to only use the node
names that the driver expects (and that gcw0.dts uses), instead of
accepting both old and new names. A follow-up patch will update the CI20
board to use the new regulator names.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221214155152.14349-1-paul@crapouillou.net


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