core: hle: kernel: Add KWorkerTask and KWorkerTaskManager.

- These primitives are used to dispatch asynchronous kernel tasks from KThread and KProcess.

src/core/CMakeLists.txt

@@ -247,6 +247,9 @@ add_library(core STATIC
     hle/kernel/k_trace.h
     hle/kernel/k_transfer_memory.cpp
     hle/kernel/k_transfer_memory.h
+    hle/kernel/k_worker_task.h
+    hle/kernel/k_worker_task_manager.cpp
+    hle/kernel/k_worker_task_manager.h
     hle/kernel/k_writable_event.cpp
     hle/kernel/k_writable_event.h
     hle/kernel/kernel.cpp