Refactor hierarchy wand/wor handling

Signed-off-by: Clifford Wolf <clifford@clifford.at>

kernel/rtlil.h

@@ -601,6 +601,7 @@ struct RTLIL::SigChunk
 	RTLIL::SigChunk &operator =(const RTLIL::SigChunk &other) = default;
 
 	RTLIL::SigChunk extract(int offset, int length) const;
+	inline int size() const { return width; }
 
 	bool operator <(const RTLIL::SigChunk &other) const;
 	bool operator ==(const RTLIL::SigChunk &other) const;