lib/rbtree.c: fix typo in comment of rb_insert_augmented()

The function name in the comment is not correct.

Link: http://lkml.kernel.org/r/20181010021344.60433-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/rbtree_augmented.h

@@ -51,8 +51,8 @@ extern void __rb_insert_augmented(struct rb_node *node,
  *
  * On insertion, the user must update the augmented information on the path
  * leading to the inserted node, then call rb_link_node() as usual and
- * rb_augment_inserted() instead of the usual rb_insert_color() call.
- * If rb_augment_inserted() rebalances the rbtree, it will callback into
+ * rb_insert_augmented() instead of the usual rb_insert_color() call.
+ * If rb_insert_augmented() rebalances the rbtree, it will callback into
  * a user provided function to update the augmented information on the
  * affected subtrees.
  */