Simplify LMR condition

Apply LMR on captures the same way it is applied on quiets

Passed Non-Reg STC:
https://tests.stockfishchess.org/tests/view/65bbf39bc865510db027a14a
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 77152 W: 19970 L: 19791 D: 37391
Ptnml(0-2): 304, 9159, 19496, 9288, 329

Passed Non-Reg LTC:
https://tests.stockfishchess.org/tests/view/65bc8889c865510db027ac9e
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 103230 W: 25997 L: 25858 D: 51375
Ptnml(0-2): 71, 11687, 27958, 11830, 69

Hit rate of removed condition (!ss->ttPv || !capture || (cutNode && (ss - 1)->moveCount > 1))
Total 1253801 Hits 1228904 Hit Rate (%) 98.0143

Hit rate of previous LMR (depth >= 2 && moveCount > 1 + rootNode && ...)
Total 1253801 Hits 727234 Hit Rate (%) 58.0023

Hit rate of simplified LMR (depth >= 2 && moveCount > 1 + rootNode)
Total 1201839 Hits 713540 Hit Rate (%) 59.3707

closes #5028

Bench: 1438224

src/search.cpp

@@ -1146,11 +1146,7 @@ Value Search::Worker::search(
         r -= ss->statScore / 15373;
 
         // Step 17. Late moves reduction / extension (LMR, ~117 Elo)
-        // We use various heuristics for the sons of a node after the first son has
-        // been searched. In general, we would like to reduce them, but there are many
-        // cases where we extend a son if it has good chances to be "interesting".
-        if (depth >= 2 && moveCount > 1 + rootNode
-            && (!ss->ttPv || !capture || (cutNode && (ss - 1)->moveCount > 1)))
+        if (depth >= 2 && moveCount > 1 + rootNode)
         {
             // In general we want to cap the LMR depth search at newDepth, but when
             // reduction is negative, we allow this move a limited search extension