Update mqttd/makefile, fix mosquitto library build bug

guowenxue

2019-07-16 4a84ac1e75212a5625ff6b83c413692bb83ce95d

 apue/2.Socket/ds18b20.c

@@ -98,5 +98,7 @@
    /* convert string value to float value */
    *temp = atof(ptr)/1000;
   
    close(fd);

    return 0;
}