Coresight changes for v5.19 This pull request includes: - Work to uniformise access to the ETMv4 registers, making it easier to look for and change register accesses. - A correction to a probing failure when looking for links between devices. - The replacement of a call to mutex_lock() with a mutex_trylock() in the panic notifier of the cpu-debug infrastructure to avoid a possible deadlock. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>