drm/nouveau: don't complain for disabled timingset entries

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_perf.c b/drivers/gpu/drm/nouveau/nouveau_perf.c
index bb50f24..b4327da 100644
--- a/drivers/gpu/drm/nouveau/nouveau_perf.c
+++ b/drivers/gpu/drm/nouveau/nouveau_perf.c
@@ -127,7 +127,8 @@
 
 	entry += ramcfg * recordlen;
 	if (entry[1] >= pm->memtimings.nr_timing) {
-		NV_WARN(dev, "timingset %d does not exist\n", entry[1]);
+		if (entry[1] != 0xff)
+			NV_WARN(dev, "timingset %d does not exist\n", entry[1]);
 		return NULL;
 	}