perf evlist: Do not pass struct record_opts to perf_evlist__prepare_workload()

Since it's only used for checking ->pipe_output, we can pass the result
directly.

Now the perf_evlist__prepare_workload() don't have a dependency of
struct perf_record_opts, it can be called from other places like perf
stat.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1362987798-24969-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-trace.c

@@ -462,7 +462,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
 
 	if (forks) {
 		err = perf_evlist__prepare_workload(evlist, &trace->opts.target,
-						    &trace->opts, argv);
+						    argv, false);
 		if (err < 0) {
 			printf("Couldn't run the workload!\n");
 			goto out_delete_evlist;