Support rectangular tx_size in recursive txfm partition

This commit supports the recursive transform block partition to
start with both square and rectangular transform block sizes.

Change-Id: Idaf29d50cb1f4876b43e5ba82c2609708c6b1926
diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index 0f831db..526cb2e 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -3366,7 +3366,7 @@
     const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
     const int mi_width = num_4x4_blocks_wide_lookup[plane_bsize];
     const int mi_height = num_4x4_blocks_high_lookup[plane_bsize];
-    const TX_SIZE max_tx_size = max_txsize_lookup[plane_bsize];
+    const TX_SIZE max_tx_size = max_txsize_rect_lookup[plane_bsize];
     const int bh = tx_size_high_unit[max_tx_size];
     const int bw = tx_size_wide_unit[max_tx_size];
     int idx, idy;
@@ -3704,7 +3704,7 @@
     const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
     const int mi_width = num_4x4_blocks_wide_lookup[plane_bsize];
     const int mi_height = num_4x4_blocks_high_lookup[plane_bsize];
-    const TX_SIZE max_tx_size = max_txsize_lookup[plane_bsize];
+    const TX_SIZE max_tx_size = max_txsize_rect_lookup[plane_bsize];
     const int bh = tx_size_high_unit[max_tx_size];
     const int bw = tx_size_wide_unit[max_tx_size];
     int idx, idy;