[media] s5p-cec: update MAINTAINERS entry

[media] s5p-cec: update MAINTAINERS entry

I would like to replace Kyungmin Park, who is no longer interested in
maintaining S5P-CEC driver. I have access to various Exynos boards. I also
already did some tests of this driver and helped enabling it on various
Exynos boards. The driver itself is no longer in staging, so lets fix the
path too and add DT bindings file pattern match. Also change the mailing
list from ARM generic to Samsung SoC specific to get more attention and
easier review in the future.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>