drm/i915/bdw: Add WaForceEnableNonCoherent label

We already implement this workaround, but it was missing its name.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Michel Thierry <michel.thierry@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 a8dc158..f1ce169 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -782,6 +782,7 @@
 	 * workaround for for a possible hang in the unlikely event a TLB
 	 * invalidation occurs during a PSD flush.
 	 */
+	/* WaForceEnableNonCoherent:bdw */
 	/* WaHdcDisableFetchWhenMasked:bdw */
 	/* WaDisableFenceDestinationToSLM:bdw (GT3 pre-production) */
 	WA_SET_BIT_MASKED(HDC_CHICKEN0,