Stop including parsenodes.h in plannodes.h

I added it by mistake in commit 7103ebb7aa.  To clean up, struct
MergeAction needs to be moved to primnodes.h from parsenodes.h.  (This
forces us to also move OverridingKind to primnodes.h).

Having to add parsenodes.h to bootstrap.h as fallout is a bit
surprising, since nothing nominally needs it there.  However, per
comments in bootscanner.l, it is needed so that YYSTYPE can be declared.
I think this only started with commit dac048f71e, but I didn't
actually verify that.

In passing, stop including parsenodes.h in tcopprot.h.  Nothing needs it
there.

Per discussion on a patch by Ashutosh Bapat.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/202311071106.6y7b2ascqjlz@alvherre.pgsql

src/backend/utils/adt/windowfuncs.c

@@ -13,6 +13,7 @@
  */
 #include "postgres.h"
 
+#include "nodes/parsenodes.h"
 #include "nodes/supportnodes.h"
 #include "utils/builtins.h"
 #include "windowapi.h"

src/include/bootstrap/bootstrap.h

@@ -15,6 +15,7 @@
 #define BOOTSTRAP_H
 
 #include "nodes/execnodes.h"
+#include "nodes/parsenodes.h"
 
 
 /*

src/include/nodes/parsenodes.h

@@ -30,13 +30,6 @@
 #include "partitioning/partdefs.h"
 
 
-typedef enum OverridingKind
-{
-	OVERRIDING_NOT_SET = 0,
-	OVERRIDING_USER_VALUE,
-	OVERRIDING_SYSTEM_VALUE,
-} OverridingKind;
-
 /* Possible sources of a Query */
 typedef enum QuerySource
 {
@@ -1681,23 +1674,6 @@ typedef struct MergeWhenClause
 	List	   *values;			/* VALUES to INSERT, or NULL */
 } MergeWhenClause;
 
-/*
- * MergeAction -
- *		Transformed representation of a WHEN clause in a MERGE statement
- */
-typedef struct MergeAction
-{
-	NodeTag		type;
-	bool		matched;		/* true=MATCHED, false=NOT MATCHED */
-	CmdType		commandType;	/* INSERT/UPDATE/DELETE/DO NOTHING */
-	/* OVERRIDING clause */
-	OverridingKind override pg_node_attr(query_jumble_ignore);
-	Node	   *qual;			/* transformed WHEN conditions */
-	List	   *targetList;		/* the target list (of TargetEntry) */
-	/* target attribute numbers of an UPDATE */
-	List	   *updateColnos pg_node_attr(query_jumble_ignore);
-} MergeAction;
-
 /*
  * TriggerTransition -
  *	   representation of transition row or table naming clause

src/include/nodes/plannodes.h

@@ -20,7 +20,6 @@
 #include "lib/stringinfo.h"
 #include "nodes/bitmapset.h"
 #include "nodes/lockoptions.h"
-#include "nodes/parsenodes.h"
 #include "nodes/primnodes.h"
 
 

src/include/nodes/primnodes.h

@@ -22,6 +22,14 @@
 #include "nodes/pg_list.h"
 
 
+typedef enum OverridingKind
+{
+	OVERRIDING_NOT_SET = 0,
+	OVERRIDING_USER_VALUE,
+	OVERRIDING_SYSTEM_VALUE,
+} OverridingKind;
+
+
 /* ----------------------------------------------------------------
  *						node definitions
  * ----------------------------------------------------------------
@@ -1718,6 +1726,25 @@ typedef struct BooleanTest
 	int			location;		/* token location, or -1 if unknown */
 } BooleanTest;
 
+
+/*
+ * MergeAction
+ *
+ * Transformed representation of a WHEN clause in a MERGE statement
+ */
+typedef struct MergeAction
+{
+	NodeTag		type;
+	bool		matched;		/* true=MATCHED, false=NOT MATCHED */
+	CmdType		commandType;	/* INSERT/UPDATE/DELETE/DO NOTHING */
+	/* OVERRIDING clause */
+	OverridingKind override pg_node_attr(query_jumble_ignore);
+	Node	   *qual;			/* transformed WHEN conditions */
+	List	   *targetList;		/* the target list (of TargetEntry) */
+	/* target attribute numbers of an UPDATE */
+	List	   *updateColnos pg_node_attr(query_jumble_ignore);
+} MergeAction;
+
 /*
  * CoerceToDomain
  *

src/include/tcop/tcopprot.h

@@ -15,7 +15,6 @@
 #define TCOPPROT_H
 
 #include "nodes/params.h"
-#include "nodes/parsenodes.h"
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"