Avoid unused identifier variable warnings. (#422)
Avoid unused identifier variable warnings. (#422)

Fixes regression introduced by 94b379e9245d31c2c1ed8344751674c0dfd6e26c.

Signed-off-by: Michel Hidalgo <2c7f9fd20fbeb41ce8894ec4653d66fa7f3b6e1a@ekumenlabs.com>
ros2/rmw_fastrtps,eProsima/ROS-RMW-Fast-RTPS-cpp,ros2/rmw_fastrtps