perf cs-etm: add error logging to cs_etm_is_etmv4()

driver inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I79882


CVE: NA

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When setting up SMT, not every process has an ETM, so the path
".../cs_etm/cpux/trcidr/trcidr0" does not exist, and the function
perf_pmu__scan_file() will return an error.
Log a error when read fails.

Signed-off-by: Junhao He <hejunhao3@huawei.com>