fd-util: use close_many() where appropriate

src/basic/fd-util.c

@@ -752,8 +752,7 @@ finish:
                 safe_close_above_stdio(original_error_fd);
 
         /* Close the copies we moved > 2 */
-        for (int i = 0; i < 3; i++)
-                safe_close(copy_fd[i]);
+        close_many(copy_fd, 3);
 
         /* Close our null fd, if it's > 2 */
         safe_close_above_stdio(null_fd);