vtree.h: remove red/black tree augmentation entirely

As agreed with phk

include/vtree.h

@@ -365,23 +365,6 @@ struct {								\
 				VRBT_RED_LEFT(VRBT_PARENT(elm, field), field) : \
 				VRBT_RED_RIGHT(VRBT_PARENT(elm, field), field))
 
-/*
- * Something to be invoked in a loop at the root of every modified subtree,
- * from the bottom up to the root, to update augmented node data.
- */
-#ifndef VRBT_AUGMENT
-#define VRBT_AUGMENT(x) do {} while (0)
-#define VRBT_AUGMENT_UP(x) do {} while (0)
-#else
-#define VRBT_AUGMENT_UP(x)						\
-	do {								\
-		while((x) != NULL) {					\
-			VRBT_AUGMENT(x);				\
-			x = VRBT_PARENT(x, field);			\
-		}							\
-	} while (0)
-#endif
-
 #define VRBT_SWAP_CHILD(head, out, in, field) do {			\
 	if (VRBT_PARENT(out, field) == NULL)				\
 		VRBT_ROOT(head) = (in);					\
@@ -400,7 +383,6 @@ struct {								\
 	VRBT_SWAP_CHILD(head, elm, tmp, field);				\
 	VRBT_LEFT(tmp, field) = (elm);					\
 	VRBT_SET_PARENT(elm, tmp, field);					\
-	VRBT_AUGMENT(elm);						\
 } while (/*CONSTCOND*/ 0)
 
 #define VRBT_ROTATE_RIGHT(head, elm, tmp, field) do {			\
@@ -412,7 +394,6 @@ struct {								\
 	VRBT_SWAP_CHILD(head, elm, tmp, field);				\
 	VRBT_RIGHT(tmp, field) = (elm);					\
 	VRBT_SET_PARENT(elm, tmp, field);					\
-	VRBT_AUGMENT(elm);						\
 } while (/*CONSTCOND*/ 0)
 
 /* Generates prototypes and inline functions */
@@ -640,7 +621,6 @@ name##_VRBT_REMOVE(struct name *head, struct type *elm)			\
 		VRBT_SET_PARENT(child, parent, field);			\
 	if (parent != NULL)						\
 		name##_VRBT_REMOVE_COLOR(head, parent, child);		\
-	VRBT_AUGMENT_UP(parent);					\
 	return (old);							\
 }
 
@@ -671,7 +651,6 @@ name##_VRBT_INSERT(struct name *head, struct type *elm)			\
 	else								\
 		VRBT_RIGHT(parent, field) = elm;				\
 	name##_VRBT_INSERT_COLOR(head, elm);				\
-	VRBT_AUGMENT_UP(elm);						\
 	return (NULL);							\
 }