perf evsel: Rearrange perf_evsel__config_leader_sampling()

	struct perf_event_attr *attr = &evsel->core.attr;

	struct evsel *leader = evsel->leader;

	if (leader == evsel || !leader->sample_read)

		return;

	/*

	 * Disable sampling for all group members other

	 * than leader in case leader 'leads' the sampling.

	 */

	if (leader != evsel && leader->sample_read) {

	attr->freq           = 0;

	attr->sample_freq    = 0;

	attr->sample_period  = 0;

	attr->write_backward = 0;

	/*

		 * We don't get sample for slave events, we make them

		 * when delivering group leader sample. Set the slave

		 * event to follow the master sample_type to ease up

		 * report.

	 * We don't get a sample for slave events, we make them when delivering

	 * the group leader sample. Set the slave event to follow the master

	 * sample_type to ease up reporting.

	 */

	attr->sample_type = leader->core.attr.sample_type;

}

}

void perf_evlist__config(struct evlist *evlist, struct record_opts *opts,

			 struct callchain_param *callchain)