Remove dead cmake code

QT_DEFINITIONS is from the Qt4 era and does not contain anything these days

kcms/kfontinst/dbus/CMakeLists.txt

-
-add_definitions(${QT_DEFINITIONS})
-
 set(fontinst_bin_SRCS FcConfig.cpp FontInst.cpp Folder.cpp Main.cpp Utils.cpp ${libkfontinstdbusiface_SRCS} )
 set(fontinst_helper_SRCS FcConfig.cpp Helper.cpp Folder.cpp Utils.cpp ${libkfontinstdbusiface_SRCS} )