[Bug] Could not enable FIFO RT scheduling policy

**Current Situation:**
During launch controller manager cannot enable real-time scheduling:

`[ros2_control_node-6] [INFO] [1751442500.999166362] [controller_manager]: update rate is 100 Hz
[ros2_control_node-6] [INFO] [1751442500.999203502] [controller_manager]: Spawning controller_manager RT thread with scheduler priority: 50
[ros2_control_node-6] [WARN] [1751442501.002182839] [controller_manager]: Could not enable FIFO RT scheduling policy: with error number <1>(Operation not permitted). See [https://control.ros.org/master/doc/ros2_control/controller_manager/doc/userdoc.html] for details on how to enable realtime scheduling.`

**Expected:**
All real-time setup launches properly.

**Workaround:**
None