Internals: Fix hash and comparison function for AstBasicDType (#4564)

src/V3Hasher.cpp

@@ -143,6 +143,7 @@ private:
     void visit(AstBasicDType* nodep) override {
         m_hash += hashNodeAndIterate(nodep, false, HASH_CHILDREN, [=]() {
             m_hash += nodep->keyword();
+            m_hash += nodep->numeric();
             m_hash += nodep->nrange().left();
             m_hash += nodep->nrange().right();
         });