Test patch for sleep on Aluminium PowerBooks

[Benjamin Herrenschmidt]

Hi !

This is an experimental patch against 2.6.9. It concerns the ATI based
Aluminium PowerBook. The nVidia based ones aren't concerned at all, and
the iBook G4 will have to wait a bit more for me to get the video wakeup
code right.

It will add sleep (suspend-to-ram) support for these machines.

It's based on various tested bits but is untested on these machines in
it's current form, so let me know.

Ben.