nv50: fixes after rebase + commits note on the code that was just pushed.

nv50: fixes after rebase + commits note on the code that was just pushed.

OK, seems a lot of people have been getting the idea that nouveau is
dying lately - I decided to commit some of the work I've been doing lately
to prove them wrong :)  Progress on my side is slow due to lack of time
mainly, but I'm still around.

Firstly, don't even bother trying to use gallium on G8x/G9x yet, it won't
work.  I've deliberately left all the necessary winsys changes out of the
commits for a very good reason - I don't know what we're going to need from
the DRM exactly yet and don't want to be continually breaking interfaces
as I discover additional requirements.  On my side, I think I've gone
through about 3 different DRM interface changes, and have just discovered
that I may need more yet.  It'd be very annoying for everyone who uses
nouveau to keep things in sync.  Once I've got it sorted - I'll commit a
lot of cool stuff. Stay tuned.

Also, don't look at the shader code.. it's horribly nasty and full of hacks,
I used it as an opportunity to learn G8x GPU programs at the same time.
New semi-decent code is in works, and will follow at some point. :)