[src/kservice.c] 修复 rt_vsnprintf 格式化后宽度不正确的问题 [src/kservice.c] 修复 rt_vsnprintf 处理 size 和 buf 为 0 极端情况的 bug (对 0 地址写入)
[src/kservice.c] 修复 rt_vsnprintf 格式化后宽度不正确的问题
[src/kservice.c] 修复 rt_vsnprintf 处理 size 和 buf 为 0 极端情况的 bug (对 0 地址写入)

Signed-off-by: MurphyZhao <5b5b4ad02826b6fdafa74f6b8c96f0e9a9b623a4@163.com>

nongxiaoming/rt-thread,weiyuliang/rt-thread,geniusgogo/rt-thread,armink/rt-thread,ArdaFu/rt-thread,hezlog/rt-thread,armink/rt-thread,weiyuliang/rt-thread,ArdaFu/rt-thread,gbcwbz/rt-thread,nongxiaoming/rt-thread,armink/rt-thread,AubrCool/rt-thread,RT-Thread/rt-thread,hezlog/rt-thread,weety/rt-thread,armink/rt-thread,nongxiaoming/rt-thread,armink/rt-thread,geniusgogo/rt-thread,armink/rt-thread,geniusgogo/rt-thread,RT-Thread/rt-thread,geniusgogo/rt-thread,weiyuliang/rt-thread,weiyuliang/rt-thread,FlyLu/rt-thread,nongxiaoming/rt-thread,geniusgogo/rt-thread,AubrCool/rt-thread,gbcwbz/rt-thread,hezlog/rt-thread,FlyLu/rt-thread,weety/rt-thread,RT-Thread/rt-thread,nongxiaoming/rt-thread,weety/rt-thread,weiyuliang/rt-thread,RT-Thread/rt-thread,ArdaFu/rt-thread,nongxiaoming/rt-thread,FlyLu/rt-thread,RT-Thread/rt-thread,weiyuliang/rt-thread,hezlog/rt-thread,weiyuliang/rt-thread,FlyLu/rt-thread,armink/rt-thread,geniusgogo/rt-thread,gbcwbz/rt-thread,hezlog/rt-thread,gbcwbz/rt-thread,nongxiaoming/rt-thread,hezlog/rt-thread,AubrCool/rt-thread,weety/rt-thread,weety/rt-thread,hezlog/rt-thread,weety/rt-thread,ArdaFu/rt-thread,RT-Thread/rt-thread,ArdaFu/rt-thread,AubrCool/rt-thread,AubrCool/rt-thread,gbcwbz/rt-thread,geniusgogo/rt-thread,RT-Thread/rt-thread,gbcwbz/rt-thread,FlyLu/rt-thread,AubrCool/rt-thread,FlyLu/rt-thread,ArdaFu/rt-thread,gbcwbz/rt-thread,AubrCool/rt-thread,ArdaFu/rt-thread,FlyLu/rt-thread,weety/rt-thread