Rewrite an operation to avoid integer out-of-range

Fix ubsan warning of the left shift operation.

Change-Id: Ib01b6ecd4a4e142948b53792a2d34153cc85784a

av1/encoder/rdopt.c

@@ -9933,7 +9933,7 @@ void av1_rd_pick_inter_mode_sb(const AV1_COMP *cpi, TileDataEnc *tile_data,
   if (sf->adaptive_mode_search) {
     if (cm->show_frame && !cpi->rc.is_src_frame_alt_ref &&
         cpi->rc.frames_since_golden >= 3)
-      if (x->pred_mv_sad[GOLDEN_FRAME] > (x->pred_mv_sad[LAST_FRAME] << 1))
+      if ((x->pred_mv_sad[GOLDEN_FRAME] >> 1) > x->pred_mv_sad[LAST_FRAME])
         mode_skip_mask[GOLDEN_FRAME] |= INTER_ALL;
   }