linux-wandboard

sh: Add notifiers chains for cpu/board code

This patch adds atomic notifier chains for pre/post
sleep events. Useful for cpu code and boards that
need to save and restore register state before and
after entering a sleep mode.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>