drm/i915/bxt: Mark Wa4x4STCOptimizationDisable as for Broxton also.

Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 88593248..cf516ad 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -951,7 +951,7 @@
 				  GEN9_ENABLE_YV12_BUGFIX);
 	}
 
-	/* Wa4x4STCOptimizationDisable:skl */
+	/* Wa4x4STCOptimizationDisable:skl,bxt */
 	WA_SET_BIT_MASKED(CACHE_MODE_1, GEN8_4x4_STC_OPTIMIZATION_DISABLE);
 
 	/* WaDisablePartialResolveInVc:skl */