"xattr" is a more meaningful name than "attr" (it resonates
with the names of the system calls), so as long as we are
moving the page to a new section, we'll change the name as well,
and retain an acl(5) link so that old references remain valid.
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>