MAINTAINERS: power: supply: add entry for S3C ADC battery driver

MAINTAINERS: power: supply: add entry for S3C ADC battery driver

The S3C ADC battery driver is a very old piece of code but still used by
(very old as well) S3C24xx platforms (iPAQ h1930/h1940/rx1950).
Currently the header file is not covered by maintainers file, so it
might look abandoned.  Add a new entry for entire S3C ADC battery driver
with Krzysztof Kozlowski as maintainer (as Krzysztof maintains still
Samsung S3C24xx platform) to indicate that some basic review can take
place.

However considering that the S3C24xx platform is quite old with only few
users currently and Krzysztof does not have the actual hardware, let's
mark the driver as "Odd fixes".

Cc: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>