Remove FAKE_CODE from use

This functionality is not used in tests and parts of it didn't work. Since
it is not actively maintained or even used, it is better to remove it.

CMakeLists.txt

@@ -154,10 +154,6 @@ if(GCOV)
   set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -lgcov")
 endif()
 
-if(FAKE_CODE)
-  set(FLAGS "${FLAGS} -DFAKE_CODE" CACHE STRING "Compilation flags"  FORCE)
-endif()
-
 if(PROFILE)
   message(STATUS "Profiling executables")
   set(FLAGS "${FLAGS} -pg " CACHE STRING "Compilation flags" FORCE)