update mqttd, add ID match support

guowenxue

2019-06-26 57b8d8022cf8444cf59cd20a25cfee491ec88799

 mqttd/etc/conf.h

@@ -37,6 +37,8 @@

typedef struct mqtt_ctx_s
{
    char          id[32];       /*  production ID */

    /* logger settings */
    char          logfile[128]; /* logger record file */
    int           loglevel;     /* logger level  */