perf diff: Refactor diff displacement possition info

Moving the position calculation into the diff command, so the position
as prepared inside struct hist_entry data and there's no need to compute
in the output display path.

Removing 'displacement' from struct perf_hpp as it is no longer needed.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1349354994-17853-3-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 6ca7407..efb8fc8 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -99,8 +99,7 @@
 size_t hists__fprintf_nr_events(struct hists *self, FILE *fp);
 
 size_t hists__fprintf(struct hists *self, struct hists *pair,
-		      bool show_displacement, bool show_header,
-		      int max_rows, int max_cols, FILE *fp);
+		      bool show_header, int max_rows, int max_cols, FILE *fp);
 
 int hist_entry__inc_addr_samples(struct hist_entry *self, int evidx, u64 addr);
 int hist_entry__annotate(struct hist_entry *self, size_t privsize);
@@ -120,7 +119,6 @@
 	size_t size;
 	u64 total_period;
 	const char *sep;
-	long displacement;
 	void *ptr;
 };