Changed per requested review to refactor to make it more logic clear.
Current output for "docker top <contianer-id> m" option,eg:
root@b2c7ec58399d:/go/src/github.com/docker/docker# docker top 755d5871ec45 am
PID TTY STAT TIME COMMAND
148 pts/0 - 0:00 bash
- - Ss+ 0:00 -
fixing issue:#30580
Signed-off-by: catinthesky <yaozaiyong@hotmail.com>