[PATCH xf86-video-ati] Update for new vgaHW API.

[Mark Kettenis]

> From: Matthieu Herrb <matthieu.herrb at laas.fr>
> Date: Sun,  1 Jan 2012 18:32:22 +0100

I really wonder why that change to the vgaHW API had to be made.  All
it does is break drivers for no benefit in the server code itself.

That said, this doesn't hurt, so:

> Signed-off-by: Matthieu Herrb <matthieu.herrb at laas.fr>

Reviewed-by: Mark Kettenis <kettenis at openbsd.org>