MAINTAINERS: Fix reviewer info for a few ROHM ICs

The email backend used by ROHM keeps labeling patches as spam.
Additionally, there have been reports of some emails been completely
dropped. Finally also the email list (or shared inbox)
linux-power@fi.rohmeurope.com inadvertly stopped working and has not
been reviwed during the past few weeks.

Remove no longer working list 'linux-power' list-entry and switch my
email to use the personal gmail account instead of the company account.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/Yk/zAHusOdf4+h06@dc73szyh141qn5ck3nwqy-3.rev.dnainternet.fi


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