Refactor: Remove unused FlatFilePos::SetNull

src/flatfile.h

@@ -13,12 +13,12 @@
 
 struct FlatFilePos
 {
-    int nFile;
-    unsigned int nPos;
+    int nFile{-1};
+    unsigned int nPos{0};
 
     SERIALIZE_METHODS(FlatFilePos, obj) { READWRITE(VARINT_MODE(obj.nFile, VarIntMode::NONNEGATIVE_SIGNED), VARINT(obj.nPos)); }
 
-    FlatFilePos() : nFile(-1), nPos(0) {}
+    FlatFilePos() {}
 
     FlatFilePos(int nFileIn, unsigned int nPosIn) :
         nFile(nFileIn),
@@ -33,7 +33,6 @@ struct FlatFilePos
         return !(a == b);
     }
 
-    void SetNull() { nFile = -1; nPos = 0; }
     bool IsNull() const { return (nFile == -1); }
 
     std::string ToString() const;