Fix $SYS/broker/publish/messages/+ counters not being updated for QoS 1, 2

Closes #1968. Thanks to promahn.

ChangeLog.txt

@@ -3,8 +3,8 @@ Broker:
 - Fix DH group not being set for TLS connections, which meant ciphers using
   DHE couldn't be used. Closes #1925. Closes #1476.
 - Fix local bridges being disconnected on SIGHUP. Closes #1942.
-
+- Fix $SYS/broker/publish/messages/+ counters not being updated for QoS 1, 2
-
+  messages. Closes #1968.
 - Fix listener not being reassociated with client when reloading a persistence
   file and `per_listener_settings true` is set and the client did not set a
   username. Closes #1891.

lib/packet_mosq.c

@@ -285,6 +285,8 @@ int packet__write(struct mosquitto *mosq)
 			mosquitto__free(packet);
 			return MOSQ_ERR_SUCCESS;
 #endif
+		}else if(((packet->command)&0xF0) == CMD_PUBLISH){
+			G_PUB_MSGS_SENT_INC(1);
 		}
 
 		/* Free data and reset values */