perf tools: Implement addr2line directly using libbfd

When the srcline sort key is used , the external addr2line utility needs
to be run for each hist entry to get the srcline info.  This can consume
quite a time if one has a huge perf.data file.

So rather than executing the external utility, implement it internally
and just call it.  We can do it since we've linked with libbfd already.

Signed-off-by: Roberto Agostino Vitillo <ravitillo@lbl.gov>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1378876173-13363-9-git-send-email-namhyung@kernel.org
[ Use a2l_data struct instead of static globals ]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>