Extend prune_ref_frames_in_tpl to speed 2

Pruning of reference frames in tpl is extended to
speed 2.

STATS_CHANGED

Change-Id: I8f083b5830f142e65e90c5cb828271bbf700d9e1
diff --git a/av1/encoder/speed_features.c b/av1/encoder/speed_features.c
index 8bbd2d5..da068b5 100644
--- a/av1/encoder/speed_features.c
+++ b/av1/encoder/speed_features.c
@@ -457,6 +457,8 @@
 
     sf->lpf_sf.prune_wiener_based_on_src_var = 1;
     sf->lpf_sf.prune_sgr_based_on_wiener = 1;
+
+    sf->tpl_sf.prune_ref_frames_in_tpl = 1;
   }
 
   if (speed >= 3) {
@@ -503,7 +505,6 @@
     sf->tpl_sf.reduce_first_step_size = 6;
     sf->tpl_sf.subpel_force_stop = QUARTER_PEL;
     sf->tpl_sf.search_method = DIAMOND;
-    sf->tpl_sf.prune_ref_frames_in_tpl = 1;
 
     sf->tx_sf.adaptive_txb_search_level = boosted ? 2 : 3;
     sf->tx_sf.tx_type_search.use_skip_flag_prediction = 2;