This patch adds xattr support to tmpfs, and a security xattr handler.  The
purpose of this is to allow udev to be mounted on tmpfs, as used currently by
Fedora.

Original patch from: Luke Kenneth Casson Leighton <lkcl@lkcl.net>.
Signed-off-by: James Morris <jmorris@redhat.com>
Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>