perf python: Switch to new perf_mmap__read_event() interface

The perf python binding still use the legacy interface.

No functional change.

Committer notes:

Tested before and after with:

  [root@jouet perf]# export PYTHONPATH=/tmp/build/perf/python
  [root@jouet perf]# tools/perf/python/twatch.py
  cpu: 0, pid: 1183, tid: 6293 { type: exit, pid: 1183, ppid: 1183, tid: 6293, ptid: 6293, time: 17886646588257}
  cpu: 2, pid: 13820, tid: 13820 { type: fork, pid: 13820, ppid: 13820, tid: 6306, ptid: 13820, time: 17886869099529}
  cpu: 1, pid: 13820, tid: 6306 { type: comm, pid: 13820, tid: 6306, comm: TaskSchedulerFo }
  ^CTraceback (most recent call last):
    File "tools/perf/python/twatch.py", line 68, in <module>
      main()
    File "tools/perf/python/twatch.py", line 40, in main
      evlist.poll(timeout = -1)
  KeyboardInterrupt
  [root@jouet perf]#

No problems found.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-3-git-send-email-kan.liang@linux.intel.com


[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>