Check whether the core is running instead of checking if it is unitialized.

This properly handles the stopping state and more accurately represents the intended check.

Source/Core/Core/State.cpp

@@ -424,7 +424,7 @@ void LoadFileStateData(const std::string& filename, std::vector<u8>& ret_data)
 
 void LoadAs(const std::string& filename)
 {
-	if (Core::GetState() == Core::CORE_UNINITIALIZED)
+	if (!Core::IsRunning())
 		return;
 
 	// Stop the core while we load the state