Lower smallnet threshold with updated eval divisors

Lower smallnet threshold with updated eval divisors

Params found after 30k spsa games at 60+0.6, with initial
values from 64k spsa games at 45+0.45

First spsa with 64k / 120k games at 45+0.45:
https://tests.stockfishchess.org/tests/view/664a561b5fc7b70b8817c663
https://tests.stockfishchess.org/tests/view/664ae88e830eb9f8866146f9

Second spsa with 30k / 120k games at 60+0.6:
https://tests.stockfishchess.org/tests/view/664be227830eb9f886615a36

Values found at 10k games at 60+0.6 also passed STC and LTC:
https://tests.stockfishchess.org/tests/view/664bf4bd830eb9f886615a72
https://tests.stockfishchess.org/tests/view/664c0905830eb9f886615abf

Passed STC:
https://tests.stockfishchess.org/tests/view/664c139e830eb9f886615af2
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 69408 W: 18216 L: 17842 D: 33350
Ptnml(0-2): 257, 8275, 17401, 8379, 392

Passed LTC:
https://tests.stockfishchess.org/tests/view/664cdaf7830eb9f886616a24
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 35466 W: 9075 L: 8758 D: 17633
Ptnml(0-2): 27, 3783, 9794, 4104, 25

closes https://github.com/official-stockfish/Stockfish/pull/5280

bench 1301287