[RFC] Use atomic plane damage property to send damage to kernel during page flip

Hi All,

With DRM subsystem support damage interface on a plane (https://lists.freedesktop.org/archives/dri-devel/2018-September/188725.html). This patch is an initial implementation to use damage on CRTC's primary plane for native backend. Damage is helpful for some drivers like VMware virtual GPU where each framebuffer changes needs to be transmitted over network, also damage might will be important on phones/tablet. Since the current state of mutter is that it doesn't use atomic interface this patch replaces drmModePageFlip() with its atomic equivalent(for atomic driver, on which underneath it is the same implementation). I would like to get feedback whether this is correct approach to use damage and should we wait for mutter to be atomic capable? Any feedback is appreciated.

Thanks, Deepak