drm/i915/bdw: Don't wait for c0 threads on forcewake

It's no longer a required workaround on BDW.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
[danvet: Move compile fix from a later patch to this one.]
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_uncore.c

@@ -112,7 +112,8 @@ static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
 		DRM_ERROR("Timed out waiting for forcewake to ack request.\n");
 
 	/* WaRsForcewakeWaitTC0:ivb,hsw */
-	__gen6_gt_wait_for_thread_c0(dev_priv);
+	if (INTEL_INFO(dev_priv->dev)->gen < 8)
+		__gen6_gt_wait_for_thread_c0(dev_priv);
 }
 
 static void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv)