IOS: Add UpdateWantDeterminism to devices

This will be useful for the USB devices to disconnect and hide any real
devices when Core::g_want_determinism is true.

Source/Core/Core/IOS/IPC.h

@@ -77,6 +77,8 @@ void Update();
 // Update Devices
 void UpdateDevices();
 
+void UpdateWantDeterminism(bool new_want_determinism);
+
 void ExecuteCommand(u32 address);
 
 void EnqueueRequest(u32 address);