perf cs-etm: Add helper cs_etm__get_pid_fmt()

mainline inclusion
from mainline-v5.11
commit 47f0d94c
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I636PS
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=47f0d94c203751ddcfdb296fcf15df20fffcef0c



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This patch adds helper function cs_etm__get_pid_fmt(), by passing
parameter "traceID", it returns the PID format.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20210213113220.292229-5-leo.yan@linaro.org
Link: https://lore.kernel.org/r/20210224164835.3497311-6-mathieu.poirier@linaro.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Junhao He <hejunhao3@huawei.com>