Seems that the typedef is not only problematic under Linux, but also under Windows. So removed it completely. I just hope that there is no clash on other platforms - we might have to work around it there then.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4825 dfc29bdd-3216-0410-991c-e03cc46cb475