Fix a unused function warning with var_tx on

Change-Id: I1e65d7e1586d8c7c65bb150b1a928cf3adf97366

vp10/decoder/decodeframe.c

diff --git a/vp10/decoder/decodeframe.c b/vp10/decoder/decodeframe.c
index 4136f14..2c2dc48 100644
--- a/vp10/decoder/decodeframe.c
+++ b/vp10/decoder/decodeframe.c
@@ -466,6 +466,7 @@
 }
 #endif  // CONFIG_VAR_TX
 
+#if !CONFIG_VAR_TX || CONFIG_SUPERTX
 static int reconstruct_inter_block(MACROBLOCKD *const xd,
 #if CONFIG_ANS
                                    const rans_dec_lut *const token_tab,
@@ -492,6 +493,7 @@
                             pd->dst.stride, eob, block_idx);
   return eob;
 }
+#endif  // !CONFIG_VAR_TX || CONFIG_SUPER_TX
 
 #if (CONFIG_SUPERTX || CONFIG_OBMC)
 static void build_mc_border(const uint8_t *src, int src_stride,