Only evaluate the PSQT part of the small net for large evals.

Thanks to Viren6 for suggesting to set complexity to 0.

STC https://tests.stockfishchess.org/tests/view/65d7d6709b2da0226a5a203f
LLR: 2.92 (-2.94,2.94) <0.00,2.00>
Total: 328384 W: 85316 L: 84554 D: 158514
Ptnml(0-2): 1414, 39076, 82486, 39766, 1450

LTC https://tests.stockfishchess.org/tests/view/65dce6d290f639b028a54d2e
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 165162 W: 41918 L: 41330 D: 81914
Ptnml(0-2): 102, 18332, 45124, 18922, 101

closes https://github.com/official-stockfish/Stockfish/pull/5083

bench: 1504003

src/nnue/nnue_accumulator.h

@@ -34,6 +34,7 @@ struct alignas(CacheLineSize) Accumulator {
     std::int16_t accumulation[2][Size];
     std::int32_t psqtAccumulation[2][PSQTBuckets];
     bool         computed[2];
+    bool         computedPSQT[2];
 };
 
 }  // namespace Stockfish::Eval::NNUE