Remove special outfuncs/readfuncs handling of RangeVar.catalogname.

Historically we skipped writing/reading this field, but that no
longer works under WRITE_READ_PARSE_PLAN_TREES since we expanded
the coverage of that option to include utility commands (787102b56).
Remove the special case and just treat this field normally.

Bump catversion out of an abundance of caution --- I do not think
we currently ever store RangeVar nodes in the catalogs, but
perhaps I'm wrong.

Per report from Pavel Stehule.

Discussion: https://postgr.es/m/CAFj8pRAYvYu-qU7-NieqRRyaQZk-yr3UjtHQ2LR62PS9M1dZMA@mail.gmail.com

src/include/catalog/catversion.h

@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202301231
+#define CATALOG_VERSION_NO	202301232
 
 #endif

src/include/nodes/primnodes.h

@@ -64,11 +64,8 @@ typedef struct RangeVar
 {
 	NodeTag		type;
 
-	/*
-	 * the catalog (database) name, or NULL; ignored for read/write, since it
-	 * is presently not semantically meaningful
-	 */
-	char	   *catalogname pg_node_attr(read_write_ignore, read_as(NULL));
+	/* the catalog (database) name, or NULL */
+	char	   *catalogname;
 
 	/* the schema name, or NULL */
 	char	   *schemaname;