fix type error for queue type

[xiaojian987]

record to char will cause queue->store_num calc error when char to negative value @shell_his_queue_add_cmd

queue->store_num -= queue->queue[queue->fp] - queue->store_front;

Char -> short int -> unsigned short int, cause error er: 0xff -> 0xFFFF

[supperthomas]

https://github.com/RT-Thread/packages/issues/1618