Adding the 'PA cnt' column grouped under data cacheline address.

It shows how many times the physical addresses changed for the hist
entry. It does not show the number of different physical addresses for
entry, because we don't store those. We only track the number of times
we got different address than we currently hold, which is not expensive
and gives similar info.

  $ perf c2c report --stdio

  #        ----------- Cacheline ----------    Total      Tot  ----- LLC Load Hitm -----
  # Index             Address  Node  PA cnt  records     Hitm    Total      Lcl      Rmt
  # .....  ..................  ....  ......  .......  .......  .......  .......  .......
  #
        0  0xffff9ad56dca0a80     0       9       10    7.69%        2        2        0
        1  0xffff9ad56dce0a80     0       9        9    7.69%        2        2        0
        2  0xffff9ad37659ad80     0       1        2    3.85%        1        1        0

  ...

  #        ----- HITM -----  -- Store Refs --  --------- Data address ---------
  #   Num      Rmt      Lcl   L1 Hit  L1 Miss              Offset  Node  PA cnt      Pid
  # .....  .......  .......  .......  .......  ..................  ....  ......  .......
  #
    -------------------------------------------------------------
        0        0        2        3        0  0xffff9ad56dca0a80
    -------------------------------------------------------------
             0.00%    0.00%   33.33%    0.00%                 0x0     0       1     2510
             0.00%    0.00%   33.33%    0.00%                 0x4     0       1     2476
             0.00%    0.00%   33.33%    0.00%                0x20     0       1        0
             0.00%  100.00%    0.00%    0.00%                0x38     0       1        0
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180309101442.9224-10-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>