update get identifier function name
update get identifier function name

ros2/rosidl,esteve/rosidl_typesupport,ros2/rosidl_typesupport,ros2/rosidl,esteve/rosidl,ros2/rosidl,ros2/rosidl,esteve/rosidl,ros2/rosidl_typesupport,ros2/rosidl_typesupport,esteve/rosidl,esteve/rosidl_typesupport,esteve/rosidl_typesupport