cmake HAS_QUADMATHLIB examples

Lewuathe/mlir-hello thirdparty/llvm-project/flang/lib/Evaluate/CMakeLists.txt :27 

add_compile_definitions(HAS_QUADMATHLIB)

Lewuathe/mlir-hello thirdparty/llvm-project/flang/runtime/Float128Math/CMakeLists.txt :82 

add_compile_definitions(HAS_QUADMATHLIB)