[Transforms][Coroutines] Add missing header path to CMakeLists.txt

Helps Visual Studio check include dependencies.

llvm/lib/Transforms/Coroutines/CMakeLists.txt

@@ -6,6 +6,9 @@ add_llvm_component_library(LLVMCoroutines
   CoroFrame.cpp
   CoroSplit.cpp
 
+  ADDITIONAL_HEADER_DIRS
+  ${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms/Coroutines
+
   DEPENDS
   intrinsics_gen
   )