[PATCH 0 of 13] DisplayState changes

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

Hi all,
this patch series imports from qemu mainstream the recent DisplayState
interface changes.
The new interface allows to have multiple frontends running at the same
time (vnc and sdl), however this series does not enable it in xend yet.
Most of the patches are just backports from qemu mainstream, adapted to
qemu-xen whenever was necessary.
The last two patches are not in qemu mainstream yet:

- patch 12 of 13 deals with changes to the xenfb frontend and backend;

- patch 13 of 13 introduces a DisplaySurface allocator interface that
allows display frontends (like xenfbfront and sdl) to provide the
DisplaySurface buffer to graphic devices whenever necessary.
Currently it is used only by xenfbfront but it is also useful for sdl.

Cheers,

Stefano Stabellini