coresight: cti: Add device tree support for v8 arch CTI

coresight: cti: Add device tree support for v8 arch CTI

The v8 architecture defines the relationship between a PE, its optional ETM
and a CTI. Unlike non-architectural CTIs which are implementation defined,
this has a fixed set of connections which can therefore be represented as a
simple tag in the device tree.

This patch defines the tags needed to create an entry for this PE/ETM/CTI
relationship, and provides functionality to implement the connection model
in the CTI driver.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200320165303.13681-7-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>