From: Davide Libenzi <davidel@xmailserver.org>

- Inline eventpoll_release() so that __fput() does not need to call in
  epoll code if the file itself is not registered inside an epoll fd

- Add <linux/types.h> inclusion due __u32 and __u64 usage

- Fix debug printf that would otherwise panic if enabled with the new
  epoll code