perf hists: Add struct perf_hpp_list argument to helper functions

Adding struct perf_hpp_list argument to following helper functions:

  void perf_hpp__setup_output_field(struct perf_hpp_list *list);
  void perf_hpp__reset_output_field(struct perf_hpp_list *list);
  void perf_hpp__append_sort_keys(struct perf_hpp_list *list);

so they could be used on hists's hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1453109064-1026-24-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>