coresight: Updates for v6.4
This is a relatively smaller update for CoreSight tracing subsystem targeting
v6.4, with the following changes:
- Removing Mathieu Poirier as MAINTAINER for the subsystem, with updates to
CREDITS for his contributions.
- Fix CoreSight ETM PMU to set the module field
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>