Internals: Rename Ast on non-node classes (#3262). No functional change.

This commit has the following replacements applied:

	s/\bAstUserInUseBase\b/VNUserInUseBase/g;
        s/\bAstAttrType\b/VAttrType/g;
        s/\bAstBasicDTypeKwd\b/VBasicDTypeKwd/g;
        s/\bAstDisplayType\b/VDisplayType/g;
        s/\bAstNDeleter\b/VNDeleter/g;
        s/\bAstNRelinker\b/VNRelinker/g;
        s/\bAstNVisitor\b/VNVisitor/g;
        s/\bAstPragmaType\b/VPragmaType/g;
        s/\bAstType\b/VNType/g;
        s/\bAstUser1InUse\b/VNUser1InUse/g;
        s/\bAstUser2InUse\b/VNUser2InUse/g;
        s/\bAstUser3InUse\b/VNUser3InUse/g;
        s/\bAstUser4InUse\b/VNUser4InUse/g;
        s/\bAstUser5InUse\b/VNUser5InUse/g;
        s/\bAstVarType\b/VVarType/g;

src/V3CUse.cpp

@@ -36,10 +36,10 @@
 // Visit within a module all nodes and data types they reference, finding
 // any classes so we can make sure they are defined when Verilated code
 // compiles
-class CUseVisitor final : public AstNVisitor {
+class CUseVisitor final : public VNVisitor {
     // NODE STATE
     //  AstNode::user1()     -> bool.  True if already visited
-    const AstUser1InUse m_inuser1;
+    const VNUser1InUse m_inuser1;
 
     // MEMBERS
     bool m_impOnly = false;  // In details needed only for implementation