drm/i915: Rework plane readout.

All non-primary planes get disabled during hw readout,
this reduces complexity and means not having to do some plane
visibility checks during the first commit.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_atomic.c

@@ -98,13 +98,6 @@ int intel_atomic_check(struct drm_device *dev,
 		return -EINVAL;
 	}
 
-	if (crtc_state &&
-	    crtc_state->quirks & PIPE_CONFIG_QUIRK_INITIAL_PLANES) {
-		ret = drm_atomic_add_affected_planes(state, &nuclear_crtc->base);
-		if (ret)
-			return ret;
-	}
-
 	ret = drm_atomic_helper_check_planes(dev, state);
 	if (ret)
 		return ret;