Core: Remove unused HostMessageID enum members.

Source/Core/Core/Core.cpp

@@ -322,7 +322,6 @@ static void CPUSetInitialExecutionState(bool force_paused = false)
     bool paused = SConfig::GetInstance().bBootToPause || force_paused;
     SetState(system, paused ? State::Paused : State::Running, true, true);
     Host_UpdateDisasmDialog();
-    Host_Message(HostMessageID::WMUserCreate);
   });
 }
 

Source/Core/Core/Host.h

@@ -43,8 +43,6 @@ enum class HostMessageID
 {
   // Begin at 10 in case there is already messages with wParam = 0, 1, 2 and so on
   WMUserStop = 10,
-  WMUserCreate,
-  WMUserSetCursor,
   WMUserJobDispatch,
 };