update mqttd hal code, instead printf by logger system

guowenxue

2019-06-26 ffa48d2a646d1deb92eaf4e13ed17d5da9bfda65

 mqttd/main.c

@@ -15,6 +15,7 @@
#include <unistd.h>
#include <getopt.h>
#include <libgen.h>
#include <string.h>

#include <mosquitto.h>