Fixed DSPTool build.

Source/DSPTool/Src/DSPTool.cpp

@@ -25,6 +25,7 @@
 u8 DSPHost_ReadHostMemory(u32 addr) { return 0; }
 void DSPHost_WriteHostMemory(u8 value, u32 addr) {}
 bool DSPHost_OnThread() { return false; }
+bool DSPHost_Wii() { return false; }
 u32 DSPHost_CodeLoaded(const u8 *ptr, int size) {return 0x1337c0de;}
 void DSPHost_InterruptRequest() {}
 void DSPHost_UpdateDebugger() {}