Cleanup redundant assertion

Change-Id: I6532e20c958d5bf6f6d73a6f076664e1b74ba055
diff --git a/av1/common/mvref_common.h b/av1/common/mvref_common.h
index d885549..5fced59 100644
--- a/av1/common/mvref_common.h
+++ b/av1/common/mvref_common.h
@@ -351,7 +351,6 @@
 #else
     assert(ref_frame_type > INTRA_FRAME);
 #endif
-    assert(ref_frame_type < TOTAL_REFS_PER_FRAME);
   }
 }