cmake FMT_HAS_MBIG_OBJ examples

NREL/EnergyPlus third_party/fmt-8.0.1/CMakeLists.txt :247 

check_cxx_compiler_flag("Wa,-mbig-obj" FMT_HAS_MBIG_OBJ)

brainflow-dev/brainflow third_party/fmt/CMakeLists.txt :252 

check_cxx_compiler_flag("-Wa,-mbig-obj" FMT_HAS_MBIG_OBJ)