drm/i915: Stop accessing crtc->state from the flip done irq

drm/i915: Stop accessing crtc->state from the flip done irq

Assuming crtc->state is pointing at the correct thing for the
async flip commit is nonsense. If we had already queued up multiple
commits this would point at the very lates crtc state even if the
older commits hadn't even happened yet.

Instead properly stage/arm the event like we do for async flips.
Since we don't need to arm multiple of these at the same time we
don't need a list like the normal vblank even processing uses.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230928152450.30109-1-ville.syrjala@linux.intel.com
Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>