fixed some warning (#5866)
fixed some warning (#5866)


nongxiaoming/rt-thread,nongxiaoming/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread