perf script: Fix memory 'threads' and 'cpus' leaks on exit

ASan reports several memory leaks while running:

  # perf test "82: Use vfs_getname probe to get syscall args filenames"

Two of these are caused by some refcounts not being decreased on
perf-script exit, namely script.threads and script.cpus.

This patch adds the missing __put calls in a new perf_script__exit
function, which is called at the end of cmd_script.

This patch concludes the fixes of all remaining memory leaks in perf
test "82: Use vfs_getname probe to get syscall args filenames".
Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Fixes: cfc8874a ("perf script: Process cpu/threads maps")
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/5ee73b19791c6fa9d24c4d57f4ac1a23609400d7.1626343282.git.rickyman7@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-script.c

@@ -2601,6 +2601,12 @@ static void perf_script__exit_per_event_dump_stats(struct perf_script *script)
 	}
 }
 
+static void perf_script__exit(struct perf_script *script)
+{
+	perf_thread_map__put(script->threads);
+	perf_cpu_map__put(script->cpus);
+}
+
 static int __cmd_script(struct perf_script *script)
 {
 	int ret;
@@ -4146,6 +4152,7 @@ int cmd_script(int argc, const char **argv)
 	zstd_fini(&(session->zstd_data));
 	evlist__free_stats(session->evlist);
 	perf_session__delete(session);
+	perf_script__exit(&script);
 
 	if (script_started)
 		cleanup_scripting();