perf tools: Add on_exit implementation

perf tools: Add on_exit implementation

on_exit() is only available in new versions of glibc.
It is not implemented in Bionic and will lead to linking errors when
compiling for Android.

Implement a wrapper for on_exit using atexit.

The implementation for on_exit is the one sent by Bernhard Rosenkraenzer in
https://lkml.org/lkml/2012/8/23/316. The configuration part from the Makefile
is different than the one from the original patch.

Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>
Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Irina Tirdea <irina.tirdea@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1349678613-7045-2-git-send-email-irina.tirdea@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>