Drop the V1 plugin API compatibility code

Signed-off-by: Gergely Nagy <algernon@keyboard.io>

src/Kaleidoscope/Heatmap.cpp

@@ -198,28 +198,6 @@ void Heatmap::update(void) {
   }
 }
 
-// Legacy V1 API
-#if KALEIDOSCOPE_ENABLE_V1_PLUGIN_API
-void Heatmap::begin() {
-  Kaleidoscope.useEventHandlerHook(legacyEventHandler);
-  Kaleidoscope.useLoopHook(legacyLoopHook);
-}
-
-Key Heatmap::legacyEventHandler(Key mapped_key, byte row, byte col, uint8_t key_state) {
-  EventHandlerResult r = ::HeatmapEffect.onKeyswitchEvent(mapped_key, row, col, key_state);
-  if (r == EventHandlerResult::OK)
-    return mapped_key;
-  return Key_NoKey;
-}
-
-void Heatmap::legacyLoopHook(bool is_post_clear) {
-  if (is_post_clear)
-    return;
-
-  ::HeatmapEffect.beforeEachCycle();
-}
-#endif
-
 }
 
 kaleidoscope::Heatmap HeatmapEffect;

src/Kaleidoscope/Heatmap.h

@@ -37,12 +37,6 @@ class Heatmap : public LEDMode {
  protected:
   void update(void) final;
 
-#if KALEIDOSCOPE_ENABLE_V1_PLUGIN_API
-  void begin();
-  static Key legacyEventHandler(Key mapped_key, byte row, byte col, uint8_t key_state);
-  static void legacyLoopHook(bool is_post_clear);
-#endif
-
  private:
   static uint16_t heatmap_[ROWS][COLS];
   static uint16_t highest_;