Simplify razor changes
Remove razoring changes from
https://github.com/official-stockfish/Stockfish/pull/5360
The mentioned patch introduced the usage of futility_margin into
razoring alongside a tune to futility_margin. It seems the elo gained in
this patch comes from the tune of futility_margin and not the
introduction of futility_margin to razoring, so simplify it away here.
Passed Non-regression STC:
https://tests.stockfishchess.org/tests/view/66606581c340c8eed7757bc8
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 169056 W: 43922 L: 43848 D: 81286
Ptnml(0-2): 438, 20288, 43034, 20298, 470
Passed Non-regression LTC:
https://tests.stockfishchess.org/tests/view/66607764c340c8eed7757c58
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 157134 W: 39805 L: 39723 D: 77606
Ptnml(0-2): 74, 17444, 43461, 17502, 86
Passed rebased Non-regression LTC:
https://tests.stockfishchess.org/tests/view/6660c696c340c8eed77580c0
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 135984 W: 34427 L: 34324 D: 67233
Ptnml(0-2): 67, 15063, 37615, 15194, 53
closes https://github.com/official-stockfish/Stockfish/pull/5366
Bench: 1150518