[PATCH v1] perf report: Name events in stats for pipe mode

[Ian Rogers <irogers@google.com>]

In stats mode PERF_RECORD_EVENT_UPDATE isn't being handled meaning the
evsels aren't named when handling pipe mode output.

Before:
```
$ perf record -e inst_retired.any -a -o - sleep 0.1|perf report --stats -i -
...
Aggregated stats:
           TOTAL events:      23358
            COMM events:       2608  (11.2%)
            EXIT events:          1  ( 0.0%)
            FORK events:       2607  (11.2%)
          SAMPLE events:        174  ( 0.7%)
           MMAP2 events:      17936  (76.8%)
            ATTR events:          2  ( 0.0%)
  FINISHED_ROUND events:          2  ( 0.0%)
        ID_INDEX events:          1  ( 0.0%)
      THREAD_MAP events:          1  ( 0.0%)
         CPU_MAP events:          1  ( 0.0%)
    EVENT_UPDATE events:          3  ( 0.0%)
       TIME_CONV events:          1  ( 0.0%)
         FEATURE events:         20  ( 0.1%)
   FINISHED_INIT events:          1  ( 0.0%)
raw 0xc0 stats:
          SAMPLE events:        174
```

After:
```
$ perf record -e inst_retired.any -a -o - sleep 0.1|perf report --stats -i -
...
Aggregated stats:
           TOTAL events:      23742
            COMM events:       2620  (11.0%)
            EXIT events:          2  ( 0.0%)
            FORK events:       2619  (11.0%)
          SAMPLE events:        165  ( 0.7%)
           MMAP2 events:      18304  (77.1%)
            ATTR events:          2  ( 0.0%)
  FINISHED_ROUND events:          2  ( 0.0%)
        ID_INDEX events:          1  ( 0.0%)
      THREAD_MAP events:          1  ( 0.0%)
         CPU_MAP events:          1  ( 0.0%)
    EVENT_UPDATE events:          3  ( 0.0%)
       TIME_CONV events:          1  ( 0.0%)
         FEATURE events:         20  ( 0.1%)
   FINISHED_INIT events:          1  ( 0.0%)
inst_retired.any stats:
          SAMPLE events:        165
```

This makes the pipe output match the regular output.

Signed-off-by: Ian Rogers <irogers@google.com>
---
This bug pre-dates commit 113f614c6dd0 ("perf report: Use
perf_tool__init()")
---
 tools/perf/builtin-report.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 1643113616f4..5c21ca33ca08 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -811,6 +811,7 @@ static void stats_setup(struct report *rep)
 	rep->tool.attr = process_attr;
 	rep->tool.sample = count_sample_event;
 	rep->tool.lost_samples = count_lost_samples_event;
+	rep->tool.event_update = perf_event__process_event_update;
 	rep->tool.no_warn = true;
 }
 
-- 
2.46.0.295.g3b9ea8a38a-goog