Rectify build error for IOS

Change-Id: Ieb5ec9994eef1003babfc28ad320cf4a114b50b8
diff --git a/test/comp_mask_variance_test.cc b/test/comp_mask_variance_test.cc
index 1e099b3..46e1e55 100644
--- a/test/comp_mask_variance_test.cc
+++ b/test/comp_mask_variance_test.cc
@@ -35,12 +35,15 @@
                                     int ref_stride, const uint8_t *mask,
                                     int mask_stride, int invert_mask);
 
+#if HAVE_SSSE3 || HAVE_SSE2 || HAVE_AVX2
 const BLOCK_SIZE kValidBlockSize[] = {
   BLOCK_8X8,   BLOCK_8X16,  BLOCK_8X32,   BLOCK_16X8,   BLOCK_16X16,
   BLOCK_16X32, BLOCK_32X8,  BLOCK_32X16,  BLOCK_32X32,  BLOCK_32X64,
   BLOCK_64X32, BLOCK_64X64, BLOCK_64X128, BLOCK_128X64, BLOCK_128X128,
   BLOCK_16X64, BLOCK_64X16
 };
+#endif
+
 typedef std::tuple<comp_mask_pred_func, BLOCK_SIZE> CompMaskPredParam;
 
 class AV1CompMaskVarianceTest