Kernel: Change WaitObject to Synchronization object. In order to better reflect RE.

src/core/CMakeLists.txt

@@ -181,14 +181,14 @@ add_library(core STATIC
     hle/kernel/svc.cpp
     hle/kernel/svc.h
     hle/kernel/svc_wrap.h
+    hle/kernel/synchronization_object.cpp
+    hle/kernel/synchronization_object.h
     hle/kernel/thread.cpp
     hle/kernel/thread.h
     hle/kernel/transfer_memory.cpp
     hle/kernel/transfer_memory.h
     hle/kernel/vm_manager.cpp
     hle/kernel/vm_manager.h
-    hle/kernel/wait_object.cpp
-    hle/kernel/wait_object.h
     hle/kernel/writable_event.cpp
     hle/kernel/writable_event.h
     hle/lock.cpp