rcutils_join_path returns a char * now. (#173)

Thus, we no longer need to cast away the const when freeing it.

Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

rmw_fastrtps_cpp/src/rmw_node.cpp

@@ -169,19 +169,19 @@ get_security_file_paths(
  std::string file_prefix("file://");
 
  for (size_t i = 0; i < num_files; i++) {
- const char * file_path = rcutils_join_path(node_secure_root, file_names[i]);
+ char * file_path = rcutils_join_path(node_secure_root, file_names[i]);
  if (!file_path) {
  return false;
  }
 
  if (rcutils_is_readable(file_path)) {
  security_files_paths[i] = file_prefix + std::string(file_path);
  } else {
- free(const_cast<char *>(file_path));
+ free(file_path);
  return false;
  }
 
- free(const_cast<char *>(file_path));
+ free(file_path);
  }
 
  return true;