MAINTAINERS: Adding help for coresight subsystem

MAINTAINERS: Adding help for coresight subsystem

With the steady stream of new features coming into the subsystem
it has been clear for some time now that help is needed.

Suzuki and Leo have worked extensively on various parts of the
project and have agreed to help.

While at it add the new location for the coresight git tree.

Acked-by: Leo Yan <leo.yan@linaro.org>
Acked-by : Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20201125223519.734388-1-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>