message: use add_llvm_library instead of add_llvm_loadable_module
  add_llvm_loadable_module() was removed here:
diff: @@ -17,6 +17,11 @@ include(AddLLVM)
  include_directories(${LLVM_INCLUDE_DIRS})
  add_definitions(${LLVM_DEFINITIONS})
  +# add_llvm_loadable_module was removed in https://reviews.llvm.org/D51748
  +if (COMMAND add_llvm_loadable_module)
  add_llvm_loadable_module(tv tv.cpp)
  +else()
  + add_llvm_library(tv MODULE tv.cpp)
  +endif()
  target_link_libraries(tv ${ALIVE_LIBS} ${Z3_LIBRARIES})
  