[dist-8x8] Fix missing if condition in previous commit

"if (x->using_dist_8x8)" was missing in the commit to master:
bdedd9878ac6e4309df8c17ad6de4d0e217280e3

Change-Id: I57c0033425afd76dfd90ea9a7116c878a56f7bc8
diff --git a/av1/encoder/encodeframe.c b/av1/encoder/encodeframe.c
index 05b45f3..19e7016 100644
--- a/av1/encoder/encodeframe.c
+++ b/av1/encoder/encodeframe.c
@@ -2443,8 +2443,10 @@
   save_context(x, &x_ctx, mi_row, mi_col, bsize, num_planes);
 
 #if CONFIG_DIST_8X8
-  if (block_size_high[bsize] <= 8 || block_size_wide[bsize] <= 8)
-    do_square_split = 0;
+  if (x->using_dist_8x8) {
+    if (block_size_high[bsize] <= 8 || block_size_wide[bsize] <= 8)
+      do_square_split = 0;
+  }
 #endif
 
   // PARTITION_NONE
@@ -3325,12 +3327,12 @@
   unsigned int pb_source_variance = UINT_MAX;
 
 #if CONFIG_DIST_8X8
-  if (block_size_high[bsize] <= 8) partition_horz_allowed = 0;
-
-  if (block_size_wide[bsize] <= 8) partition_vert_allowed = 0;
-
-  if (block_size_high[bsize] <= 8 || block_size_wide[bsize] <= 8)
-    do_square_split = 0;
+  if (x->using_dist_8x8) {
+    if (block_size_high[bsize] <= 8) partition_horz_allowed = 0;
+    if (block_size_wide[bsize] <= 8) partition_vert_allowed = 0;
+    if (block_size_high[bsize] <= 8 || block_size_wide[bsize] <= 8)
+      do_square_split = 0;
+  }
 #endif
 
   // PARTITION_NONE
@@ -3673,9 +3675,11 @@
   int vertab_partition_allowed = ext_partition_allowed;
 
 #if CONFIG_DIST_8X8
-  if (block_size_high[bsize] <= 8 || block_size_wide[bsize] <= 8) {
-    horzab_partition_allowed = 0;
-    vertab_partition_allowed = 0;
+  if (x->using_dist_8x8) {
+    if (block_size_high[bsize] <= 8 || block_size_wide[bsize] <= 8) {
+      horzab_partition_allowed = 0;
+      vertab_partition_allowed = 0;
+    }
   }
 #endif
 
@@ -3917,9 +3921,11 @@
   }
 
 #if CONFIG_DIST_8X8
-  if (block_size_high[bsize] <= 16 || block_size_wide[bsize] <= 16) {
-    partition_horz4_allowed = 0;
-    partition_vert4_allowed = 0;
+  if (x->using_dist_8x8) {
+    if (block_size_high[bsize] <= 16 || block_size_wide[bsize] <= 16) {
+      partition_horz4_allowed = 0;
+      partition_vert4_allowed = 0;
+    }
   }
 #endif