Move HOSTFS_SUPER_MAGIC to <linux/magic.h> to be with it's magical
friends from other file systems.
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>