perf test shell stat_bpf_counters: Fix test on Intel

As of now, bpf counters (bperf) don't support event groups.  But the
default perf stat includes topdown metrics if supported (on recent Intel
machines) which require groups.  That makes perf stat exiting.

  $ sudo perf stat --bpf-counter true
  bpf managed perf events do not yet support groups.

Actually the test explicitly uses cycles event only, but it missed to
pass the option when it checks the availability of the command.

Fixes: 2c0cb9f5 ("perf test: Add a shell test for 'perf stat --bpf-counters' new option")
Reviewed-by: Song Liu <song@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: bpf@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230825164152.165610-2-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/shell/stat_bpf_counters.sh

@@ -22,10 +22,10 @@ compare_number()
 }
 
 # skip if --bpf-counters is not supported
-if ! perf stat --bpf-counters true > /dev/null 2>&1; then
+if ! perf stat -e cycles --bpf-counters true > /dev/null 2>&1; then
 	if [ "$1" = "-v" ]; then
 		echo "Skipping: --bpf-counters not supported"
-		perf --no-pager stat --bpf-counters true || true
+		perf --no-pager stat -e cycles --bpf-counters true || true
 	fi
 	exit 2
 fi