Add lint error on importing package within a class (#5634) (#5679)

src/V3LinkParse.cpp

@@ -893,6 +893,13 @@ class LinkParseVisitor final : public VNVisitor {
         }
         iterateChildren(nodep);
     }
+    void visit(AstPackageImport* nodep) override {
+        cleanFileline(nodep);
+        if (m_modp && !m_ftaskp && VN_IS(m_modp, Class)) {
+            nodep->v3error("Import statement directly within a class scope is illegal");
+        }
+        iterateChildren(nodep);
+    }
 
     void visit(AstNode* nodep) override {
         // Default: Just iterate