[CMake] qt4_add_translation from build directory

[Norbert Bokor]

oops, i found the problem: the .qm files were listed in .qrc :)
> I have a small Qt project, with two .ts files. In the CMakeLists.txt I 
> have the line QT4_ADD_TRANSLATION(qmfiles ${TRANSLATIONFILES}).
> It works perfectly when i run 'cmake . && make' from the source 
> directory, but if I do the same from an other directory, I get an 
> error from make. The problem is that the .qm files are created in the 
> build directory, but make looks for them in the source directory. Is 
> it a bug, or should I modify something?