update release_notes

doc/release_notes.rst

@@ -73,6 +73,7 @@ controller_manager
 * The support for the ``description`` parameter for loading the URDF was removed (`#1358 <https://github.com/ros-controls/ros2_control/pull/1358>`_).
 * The ``--controller-type`` or ``-t`` spawner arg is removed. Now the controller type is defined in the controller configuration file with ``type`` field (`#1639 <https://github.com/ros-controls/ros2_control/pull/1639>`_).
 * The ``--namespace`` or ``-n`` spawner arg is deprecated. Now the spawner namespace can be defined using the ROS 2 standard way (`#1640 <https://github.com/ros-controls/ros2_control/pull/1640>`_).
+* The spawner now supports the ``--controller-ros-args`` argument to pass the ROS 2 node arguments to the controller node to be able to remap topics, services and etc (`#1713 <https://github.com/ros-controls/ros2_control/pull/1713>`_).
 
 hardware_interface
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