UPSTREAM: coresight: tmc-etr: Introduce the notion of process ID to ETR devices

In preparation to support CPU-wide trace scenarios, introduce the notion
of process ID to ETR devices.  That way events monitoring the same process
can use the same etr_buf, allowing multiple CPUs to use the same sink.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

(Upstream commit ef848e463ac9052be620757579cfa0aa975e97ea).

Bug: 140266694
Change-Id: Ic74a1b5057e25f89b86a2fab5217d849ae186534
Signed-off-by: Yabin Cui <yabinc@google.com>