esp_bt_controller_enable() function

- ESP_OK: Success - ESP_ERR_INVALID_STATE: Invalid Bluetooth Controller state - ESP_ERR_INVALID_ARG: Invalid arguments

1. Bluetooth Controller cannot be enabled in `ESP_BT_CONTROLLER_STATUS_IDLE` status. It has to be initialized first. 2. Due to a known issue, you cannot call `esp_bt_controller_enable()` for the second time to change the Controller mode dynamically. To change the Controller mode, call `esp_bt_controller_disable()` and then call `esp_bt_controller_enable()` with the new mode.