Here are some trivial pull requests:
1. remove useless function declaration do_assoc_move_next_bucket()
2. declare item_lock_hashpower as a static variable
3. remove useless function item_link
4. code clean: remove unnecessary argument
5. bugfix: size.c: struct size error
6. rm_lru_maintainer_initialized
7. remove unnecessary HAVE_UNISTD_H check
Please take a look and thanks very much!