drm/i915: do not wait for vblank when crtc is off

This can happen when turning off a sprite plane. Because the crtc state
is not yet always swapped correctly and transitional helpers are used
the crtc state cannot be relied on.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/intel_display.c

@@ -13768,7 +13768,7 @@ static void intel_finish_crtc_commit(struct drm_crtc *crtc)
 
 	intel_runtime_pm_put(dev_priv);
 
-	if (intel_crtc->atomic.wait_vblank)
+	if (intel_crtc->atomic.wait_vblank && intel_crtc->active)
 		intel_wait_for_vblank(dev, intel_crtc->pipe);
 
 	intel_frontbuffer_flip(dev, intel_crtc->atomic.fb_bits);