Move Wii FS content init to happen after Boot

Initialising Wii filesystem contents should be done after Boot and
not in HW to ensure that we operate with the correct title context
and to make sure required title directories exist (so that Movie and
Netplay code can copy data from and to the temporary NAND).

Source/Core/Core/Core.cpp

@@ -517,6 +517,12 @@ static void EmuThread(std::unique_ptr<BootParameters> boot)
   if (!CBoot::BootUp(std::move(boot)))
     return;
 
+  // Initialise Wii filesystem contents.
+  // This is done here after Boot and not in HW to ensure that we operate
+  // with the correct title context since save copying requires title directories to exist.
+  Common::ScopeGuard wiifs_guard{Core::CleanUpWiiFileSystemContents};
+  Core::InitializeWiiFileSystemContents();
+
   // This adds the SyncGPU handler to CoreTiming, so now CoreTiming::Advance might block.
   Fifo::Prepare();