qemu qxl kms driver

Hi,

This is a KMS driver for the QXL virtual hw device shipped in qemu.

The first patch just adds some ttm symbol exports, the second contains
the driver.

Its also in my git repo here
http://cgit.freedesktop.org/~airlied/linux/log/?h=qxl-ups...

The userspace driver is here
http://cgit.freedesktop.org/~airlied/xf86-video-qxl/log/?...

There is also a header file addition to libdrm:
http://cgit.freedesktop.org/~airlied/drm/log/?h=qxl-kms
though I could probably drop it into the ddx at this point, since
there isn't really any DRI usefulness on this hw yet. Though
maybe we can save a copy or two in some fast paths.

Dave.