app/eventdev: remove unnecessary barrier in pipeline test

For "processed_pkts" function, no operations should keep the order that
being executed before loading "worker[i].processed_pkts".

Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Acked-by: Pavan Nikhilesh <pbhagavatula@marvell.com>

app/test-eventdev/test_pipeline_common.c

@@ -44,7 +44,6 @@ processed_pkts(struct test_pipeline *t)
 	uint8_t i;
 	uint64_t total = 0;
 
-	rte_smp_rmb();
 	for (i = 0; i < t->nb_workers; i++)
 		total += t->worker[i].processed_pkts;