feat(ble/bluedroid): Add getter for BLE GATTS callback

components/bt/host/bluedroid/api/esp_gatts_api.c

@@ -29,6 +29,11 @@ esp_err_t esp_ble_gatts_register_callback(esp_gatts_cb_t callback)
     return (btc_profile_cb_set(BTC_PID_GATTS, callback) == 0 ? ESP_OK : ESP_FAIL);
 }
 
+esp_gatts_cb_t esp_ble_gatts_get_callback(void)
+{
+    return (esp_gatts_cb_t) btc_profile_cb_get(BTC_PID_GATTS);
+}
+
 esp_err_t esp_ble_gatts_app_register(uint16_t app_id)
 {
     btc_msg_t msg = {0};

components/bt/host/bluedroid/api/include/api/esp_gatts_api.h

@@ -304,6 +304,16 @@ typedef void (* esp_gatts_cb_t)(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_
  */
 esp_err_t esp_ble_gatts_register_callback(esp_gatts_cb_t callback);
 
+/**
+ * @brief           This function is called to get the current application callbacks
+ *                  with BTA GATTS module.
+ *
+ * @return
+ *                  - esp_gatts_cb_t : current callback
+ *
+ */
+esp_gatts_cb_t esp_ble_gatts_get_callback(void);
+
 /**
  * @brief           This function is called to register application identifier
  *