perf sched: Fix 'perf sched latency' output on 32-bit systems

Before:

  -----------------------------------------------------------------------------------
   Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
  -----------------------------------------------------------------------------------
   perf              |4853313.251 ms |       10 | avg:    0.046 ms | max:    0.337 ms |
   flush-8:0         |2426659.202 ms |        5 | avg:    0.015 ms | max:    0.016 ms |
   sleep             |485331.966 ms |        1 | avg:    0.012 ms | max:    0.012 ms |
   ksoftirqd/1       |485331.320 ms |        1 | avg:    0.005 ms | max:    0.005 ms |
  -----------------------------------------------------------------------------------
   TOTAL:            |8250635.739 ms |       17 |
  ---------------------------------------------

After:

  -----------------------------------------------------------------------------------
   Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
  -----------------------------------------------------------------------------------
   perf              |    0.206 ms |       10 | avg:    0.046 ms | max:    0.337 ms |
   flush-8:0         |    2.680 ms |        5 | avg:    0.015 ms | max:    0.016 ms |
   sleep             |    0.662 ms |        1 | avg:    0.012 ms | max:    0.012 ms |
   ksoftirqd/1       |    0.015 ms |        1 | avg:    0.005 ms | max:    0.005 ms |
  -----------------------------------------------------------------------------------
   TOTAL:            |    3.563 ms |       17 |
  ---------------------------------------------

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>