BTM_BleSetConnectableMode() function

* Function BTM_BleSetConnectableMode * Description This function is called to set BLE connectable mode for a * peripheral device. * Parameters connectable_mode: directed connectable mode, or non-directed.It can * be BTM_BLE_CONNECT_EVT, BTM_BLE_CONNECT_DIR_EVT or * BTM_BLE_CONNECT_LO_DUTY_DIR_EVT * Returns BTM_ILLEGAL_VALUE if controller does not support BLE. * BTM_SUCCESS is status set successfully; otherwise failure.