In following patches we will allow to switch percent type even for stdio
annotation outputs. Adding the percent type value into the annotation
outputs title.

  $ perf annotate --stdio
   Percent         |      Sou ... instructions:u } (2805 samples, percent: local period)
  --------------------------- ... ------------------------------------------------------
  ...

  $ perf annotate --stdio2
  Samples: 2K of events 'anon ...  count (approx.): 156525487, [percent: local period]
  safe_write.c() /usr/bin/yes
  Percent
  ...
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-19-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>