Add TT21100 touchscreen component (#4793)

Co-authored-by: Rajan Patel <rpatel3001@gmail.com>
Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

esphome/components/tt21100/binary_sensor/tt21100_button.h

@@ -0,0 +1,28 @@
+#pragma once
+
+#include "esphome/components/binary_sensor/binary_sensor.h"
+#include "esphome/components/tt21100/touchscreen/tt21100.h"
+#include "esphome/core/component.h"
+#include "esphome/core/helpers.h"
+
+namespace esphome {
+namespace tt21100 {
+
+class TT21100Button : public binary_sensor::BinarySensor,
+                      public Component,
+                      public TT21100ButtonListener,
+                      public Parented<TT21100Touchscreen> {
+ public:
+  void setup() override;
+  void dump_config() override;
+
+  void set_index(uint8_t index) { this->index_ = index; }
+
+  void update_button(uint8_t index, uint16_t state) override;
+
+ protected:
+  uint8_t index_;
+};
+
+}  // namespace tt21100
+}  // namespace esphome