MINOR: stream: Remove the lock on the proxy to update time stats

swrate_add() is now thread-safe. So the lock on the proxy is no longer needed to
update q_time, c_time, d_time and t_time.

(cherry picked from commit b927a9d8668208eb7a34f88e8db916262d0e698c)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/stream.c b/src/stream.c
index c76d010..a85b723 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -2795,12 +2795,10 @@
 		swrate_add(&srv->counters.d_time, TIME_STATS_SAMPLES, t_data);
 		swrate_add(&srv->counters.t_time, TIME_STATS_SAMPLES, t_close);
 	}
-	HA_SPIN_LOCK(PROXY_LOCK, &s->be->lock);
 	swrate_add(&s->be->be_counters.q_time, TIME_STATS_SAMPLES, t_queue);
 	swrate_add(&s->be->be_counters.c_time, TIME_STATS_SAMPLES, t_connect);
 	swrate_add(&s->be->be_counters.d_time, TIME_STATS_SAMPLES, t_data);
 	swrate_add(&s->be->be_counters.t_time, TIME_STATS_SAMPLES, t_close);
-	HA_SPIN_UNLOCK(PROXY_LOCK, &s->be->lock);
 }
 
 /*