thermal: Remove Amit Kucheria from MAINTAINERS

Amit Kucheria has not been participating in kernel development in any
way or form for quite some time, so it is not useful to list him as a
designated reviewer for the thermal subsystem or as the thermal zone DT
binding maintainer.

Remove him from the THERMAL entry in MAINTAINERS and list Daniel Lezcano
as the new thermal zone DT binding maintainer.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Amit Kucheria <amitk@kernel.org>