coresight: etm4x: Expose trcdevarch via sysfs

mainline inclusion
from mainline-v5.11-rc5
commit 4211bfce
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5YCYK
CVE: NA

Reference: https://lore.kernel.org/r/20210201181351.1475223-23-mathieu.poirier@linaro.org

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Expose the TRCDEVARCH register via the sysfs for component
detection. Given that the TRCIDR1 may not completely identify
the ETM component and instead need to use TRCDEVARCH, expose
this via sysfs for tools to use it for identification.

Link: https://lore.kernel.org/r/20210110224850.1880240-21-suzuki.poulose@arm.com


Cc: Mike Leach <mike.leach@linaro.org>
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/20210201181351.1475223-23-mathieu.poirier@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>