update mqttd, modify default Qos to 0

Guo Wenxue

2019-06-26 d5ad51c46446e261d964515ca3a6bddb8559e014

 mqttd/hal/hal.c

@@ -16,12 +16,15 @@
int hal_init(void)
{
    init_led(); 
    
    relay_init();

#if 0
    if( sht2x_init() < 0 )
    {
        log_err("Initialise SHT20 failure\n");
        return -2;
    } 
#endif
    
    return 0;
}