Rewrite NNUE evaluation adjustments

Rewrite NNUE evaluation adjustments

Make the eval code in the evaluate_nnue.cpp more similar to the rest of the codebase:

* remove multiple variable assignment
* make if conditions explicit and indent on multiple lines

passed STC
LLR: 2.93 (-2.94,2.94) <-2.50,0.50>
Total: 59032 W: 14834 L: 14751 D: 29447
Ptnml(0-2): 176, 6310, 16459, 6397, 174
https://tests.stockfishchess.org/tests/view/616f250540f619782fd4f76d

closes https://github.com/official-stockfish/Stockfish/pull/3753

No functional change