coexist: enable coexist when wifi&bt are enabled, disable coexist when one of wifi&bt is disabled.

components/esp32/include/esp_coexist.h

@@ -25,6 +25,11 @@ extern "C" {
  */
 esp_err_t coex_init(void);
 
+/**
+ * @brief De-init software coexist
+ */
+void coex_deinit(void);
+
 /**
  * @brief Get software coexist enable or not
  *

components/esp32/include/esp_wifi.h

@@ -130,6 +130,7 @@ esp_err_t esp_wifi_init(wifi_init_config_t *config);
   *         Free all resource allocated in esp_wifi_init and stop WiFi task
   *
   * @attention 1. This API should be called if you want to remove WiFi driver from the system
+  * @attention 2. This API can not be called yet and will be done in the future.
   *
   * @return ESP_OK: succeed
   */