Non-functional Fixes & Updates

Fixes a missing default slot for dbg_extremes of, removes a extra newline, and
updates SE elo estimate from
https://tests.stockfishchess.org/tests/view/664ebd1e928b1fb18de4e4b7 while we
are at it.

closes https://github.com/official-stockfish/Stockfish/pull/5446

No functional change

src/search.cpp

@@ -462,8 +462,8 @@ void Search::Worker::iterative_deepening() {
             double bestMoveInstability = 1 + 1.88 * totBestMoveChanges / threads.size();
             double recapture           = limits.capSq == rootMoves[0].pv[0].to_sq() ? 0.955 : 1.005;
 
-            double totalTime = mainThread->tm.optimum() * fallingEval * reduction
-                             * bestMoveInstability * recapture;
+            double totalTime =
+              mainThread->tm.optimum() * fallingEval * reduction * bestMoveInstability * recapture;
 
             // Cap used time in case of a single legal move for a better viewer experience
             if (rootMoves.size() == 1)
@@ -1068,8 +1068,8 @@ moves_loop:  // When in check, search starts here
         // We take care to not overdo to avoid search getting stuck.
         if (ss->ply < thisThread->rootDepth * 2)
         {
-            // Singular extension search (~94 Elo). If all moves but one fail low on a
-            // search of (alpha-s, beta-s), and just one fails high on (alpha, beta),
+            // Singular extension search (~76 Elo, ~170 nElo). If all moves but one fail
+            // low on a search of (alpha-s, beta-s), and just one fails high on (alpha, beta),
             // then that move is singular and should be extended. To verify this we do
             // a reduced search on the position excluding the ttMove and if the result
             // is lower than ttValue minus a margin, then we will extend the ttMove.