Simplify Away Second Razoring Number
This patch simplifies away the second razoring number and adds a small offset to compensate.
Passed STC non regression:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 169600 W: 43837 L: 43764 D: 81999
Ptnml(0-2): 397, 19909, 44131, 19950, 413
https://tests.stockfishchess.org/tests/view/6a7481672cf557d58a2e20ee
Passed LTC non regression:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 28332 W: 7450 L: 7241 D: 13641
Ptnml(0-2): 5, 2895, 8169, 3080, 17
https://tests.stockfishchess.org/tests/view/6a78946ea7e815d01b56019f
On new master, doesn't hurt matetrack results significantly:
Master results on 1th 1m nodes:
Total FENs: 6554
Found mates: 3160
Best mates: 2218
New results on 1th 1m nodes:
Total FENs: 6554
Found mates: 3180
Best mates: 2215
On new master, doesn't hurt matedtrack results significantly either:
Master results on 1th 1m nodes:
Total FENs: 6536
Found mates: 3500
Best mates: 2856
New results on 1th 1m nodes:
Total FENs: 6536
Found mates: 3506
Best mates: 2859
Maybe even improves matetrack/matedtrack :)
closes https://github.com/official-stockfish/Stockfish/pull/7044
Bench: 2516158