Refine do_adapt_scan's logic

Change-Id: I6d68f03e3f9b1e40b05503f6bb4055e2fd870893

av1/common/scan.h

@@ -93,7 +93,7 @@ static INLINE const SCAN_ORDER *get_default_scan(TX_SIZE tx_size,
 static INLINE int do_adapt_scan(TX_SIZE tx_size, TX_TYPE tx_type) {
   (void)tx_size;
 #if CONFIG_EXT_TX
-  if (tx_size == TX_32X32 && tx_type != DCT_DCT) return 0;
+  if (tx_size_2d[tx_size] >= 1024 && tx_type != DCT_DCT) return 0;
   return tx_type < IDTX;
 #else
   (void)tx_type;