remove ament_export_link_flags() for atomic operations.

Signed-off-by: Tomoya.Fujita <tomoya.fujita825@gmail.com>

Author: fujitatomoya

CMakeLists.txt

@@ -100,8 +100,10 @@ target_link_libraries(${PROJECT_NAME} ${CMAKE_DL_LIBS})
 check_library_exists(atomic __atomic_load_8 "" HAVE_LIBATOMICS)
 
 if(HAVE_LIBATOMICS AND NOT WIN32)
-  # Exporting link flag since it won't pass ament_export_libraries() existence check
-  ament_export_link_flags("-latomic")
+  # Link libatomic into rcutils for fault injection atomic operations.
+  # Don't export it - downstream packages get atomic symbols transitively
+  # through librcutils.so, avoiding library resolution issues in containerized
+  # environments. See https://github.com/ros2/rcutils/issues/525
   target_link_libraries(${PROJECT_NAME} atomic)
 endif()