#227 Fix (2nd Attempt) Unwanted User Demotion

Okay, I've used simple_select method and shrinked the code using ternary operator.
Is it acceptable now?

Reference of issue:
https://github.com/mybb/mybb/issues/227
[Ternary operators](http://en.wikipedia.org/wiki/Ternary_operation) aren't allowed. Use ```if``` and ```else``` instead.

http://docs.mybb.com/Coding_Standards.html#Control_Structures