perf test: Avoid uncore_imc/clockticks in uniquification test

perf test: Avoid uncore_imc/clockticks in uniquification test

The detection of uncore_imc may happen for free running PMUs and the
clockticks event may be present on uncore_clock. Rewrite the test to
detect duplicated/deduplicated events from perf list, not hardcoded to
uncore_imc.

If perf stat fails then assume it is permissions and skip the test.

Committer testing:

Before:

  root@x1:~# perf test -vv uniquifyi
   96: perf stat events uniquifying:
  --- start ---
  test child forked, pid 220851
  stat event uniquifying test
  grep: Unmatched [, [^, [:, [., or [=
  Event is not uniquified [Failed]
  perf stat -e clockticks -A -o /tmp/__perf_test.stat_output.X7ChD -- true
  # started on Fri Sep 19 16:48:38 2025

   Performance counter stats for 'system wide':

  CPU0            2,310,956      uncore_clock/clockticks/

         0.001746771 seconds time elapsed

  ---- end(-1) ----
   96: perf stat events uniquifying                                    : FAILED!
  root@x1:~#

After:

  root@x1:~# perf test -vv uniquifyi
   96: perf stat events uniquifying:
  --- start ---
  test child forked, pid 222366
  Uniquification of PMU sysfs events test
  Testing event uncore_imc_free_running/data_read/ is uniquified to uncore_imc_free_running_0/data_read/
  Testing event uncore_imc_free_running/data_total/ is uniquified to uncore_imc_free_running_0/data_total/
  Testing event uncore_imc_free_running/data_write/ is uniquified to uncore_imc_free_running_0/data_write/
  Testing event uncore_imc_free_running/data_read/ is uniquified to uncore_imc_free_running_1/data_read/
  Testing event uncore_imc_free_running/data_total/ is uniquified to uncore_imc_free_running_1/data_total/
  Testing event uncore_imc_free_running/data_write/ is uniquified to uncore_imc_free_running_1/data_write/
  ---- end(0) ----
   96: perf stat events uniquifying                                    : Ok
  root@x1:~#

Fixes: 070b315333ee942f ("perf test: Restrict uniquifying test to machines with 'uncore_imc'")
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>