Fix memset/memcpy warnings

No functional change.

src/nnue/nnue_accumulator.h

@@ -12,9 +12,9 @@ namespace Eval::NNUE {
   struct alignas(32) Accumulator {
     std::int16_t
         accumulation[2][kRefreshTriggers.size()][kTransformedFeatureDimensions];
-    Value score = VALUE_ZERO;
-    bool computed_accumulation = false;
-    bool computed_score = false;
+    Value score;
+    bool computed_accumulation;
+    bool computed_score;
   };
 
 }  // namespace Eval::NNUE

src/types.h

@@ -294,9 +294,6 @@ enum PieceSquare : uint32_t
 struct ExtPieceSquare
 {
     PieceSquare from[COLOR_NB];
-
-    ExtPieceSquare() {}
-    ExtPieceSquare(PieceSquare fw, PieceSquare fb) : from{fw, fb} {}
 };
 
 // Array for finding the PieceSquare corresponding to the piece on the board