drm/i915: Do no set Stencil Cache eviction LRA w/a on gen7+

I've flagged this while reviewing the first version and Ken Graunke
fixed it up in v2, but unfortunately Dave Airlie picked up the wrong
version.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: stable@kernel.org
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -398,10 +398,8 @@ static int init_render_ring(struct intel_ring_buffer *ring)
 			return ret;
 	}
 
-	if (INTEL_INFO(dev)->gen >= 6) {
-		I915_WRITE(INSTPM,
-			   INSTPM_FORCE_ORDERING << 16 | INSTPM_FORCE_ORDERING);
 
+	if (IS_GEN6(dev)) {
 		/* From the Sandybridge PRM, volume 1 part 3, page 24:
 		 * "If this bit is set, STCunit will have LRA as replacement
 		 *  policy. [...] This bit must be reset.  LRA replacement
@@ -411,6 +409,11 @@ static int init_render_ring(struct intel_ring_buffer *ring)
 			   CM0_STC_EVICT_DISABLE_LRA_SNB << CM0_MASK_SHIFT);
 	}
 
+	if (INTEL_INFO(dev)->gen >= 6) {
+		I915_WRITE(INSTPM,
+			   INSTPM_FORCE_ORDERING << 16 | INSTPM_FORCE_ORDERING);
+	}
+
 	return ret;
 }