Adjust psnr threshold in fwd-kf test

Change-Id: I0b13da3d92482738806f4178a6c0afa78bdd7627
diff --git a/test/fwd_kf_test.cc b/test/fwd_kf_test.cc
index 2a37ff1..5084048 100644
--- a/test/fwd_kf_test.cc
+++ b/test/fwd_kf_test.cc
@@ -23,7 +23,7 @@
 } FwdKfTestParam;
 
 const FwdKfTestParam kTestParams[] = {
-  { 4, 34.0 },  { 6, 33.3 },  { 8, 33.0 },
+  { 4, 33.4 },  { 6, 32.9 },  { 8, 32.6 },
   { 12, 32.4 }, { 16, 32.3 }, { 18, 32.1 }
 };