o add missing files

tools/bsnes/system/interface/interface.hpp

@@ -0,0 +1,8 @@
+class Interface {
+public:
+  virtual void video_refresh(uint16_t *data, unsigned pitch, unsigned *line, unsigned width, unsigned height) {}
+  virtual void audio_sample(uint16_t l_sample, uint16_t r_sample) {}
+  virtual void input_poll() {}
+  virtual int16_t input_poll(unsigned deviceid, unsigned id) { return 0; }
+};
+