staging: gma500: Intel GMA500 staging driver

This is an initial staging driver for the GMA500. It's been stripped out
of the PVR drivers and crunched together from various bits of code and
different kernels.

Currently it's unaccelerated but still pretty snappy even compositing with
the frame buffer X server.

Lots of work is needed to rework the ttm and bo interfaces from being
ripped out and then 2D acceleration wants putting back for framebuffer and
somehow eventually via DRM.

There is no support for the parts without open source userspace (video
accelerators, 3D) as per kernel policy.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>