This patch fixes a bug in the PPC440 pagetable attributes that breaks swap
support.  It also adds some notes on the PPC440 attribute fields.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com> for CELF
Signed-off-by: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>