coresight: etm4x: Run arch feature detection on the CPU

commit 2156f1a9ccc5a6d5aa81ef0da952e7fe9901b6ff from
git@git.assembla.com:cavium/WindRiver.linux.git

As we are about to add support for system register based devices,
we don't get an AMBA pid. So, the detection code could check
the system registers running on the CPU to check for the architecture
specific features. Thus we move the arch feature detection to
run on the CPU. We cannot always read the PID from the HW, as the
PID could be overridden by DT for broken devices. So, use the
PID from AMBA layer if available.

Link: https://lore.kernel.org/r/20210110224850.1880240-25-suzuki.poulose@arm.com


Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: liuqi115@huawei.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210201181351.1475223-27-mathieu.poirier@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>