perf sched timehist: Show total wait times for summary

perf sched timehist: Show total wait times for summary

When --state option is given, the summary will show total run, sleep,
iowait, preempt and delay time instead of statistics of runtime.

  $ perf sched timehist -s --state

  Wait-time summary
            comm  parent sched-in run-time  sleep iowait preempt delay
                          (count)   (msec) (msec) (msec)  (msec) (msec)
  ---------------------------------------------------------------------
       systemd[1]      0        3    0.497   1.685 0.000   0.000 0.061
   ksoftirqd/0[3]      2       21    0.434 989.948 0.000   0.000 0.325
   rcu_preempt[7]      2       28    0.386 993.211 0.000   0.000 0.712
  migration/0[10]      2       12    0.126  50.174 0.000   0.000 0.044
   watchdog/0[11]      2        1    0.009   0.000 0.000   0.000 0.016
  migration/1[13]      2        2    0.029  11.755 0.000   0.000 0.007
  <SNIP>

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170113104523.31212-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>