more error checks - 'a' to 'd' complete

MagickCore/splay-tree.c

diff --git a/MagickCore/splay-tree.c b/MagickCore/splay-tree.c
index 1507c63..3752930 100644
--- a/MagickCore/splay-tree.c
+++ b/MagickCore/splay-tree.c
@@ -583,6 +583,8 @@
 %
 %  DeleteNodeFromSplayTree() deletes a node from the splay-tree.
 %
+%  Returns MagickTrue is the option is found and deleted from the Options.
+%
 %  The format of the DeleteNodeFromSplayTree method is:
 %
 %      MagickBooleanType DeleteNodeFromSplayTree(SplayTreeInfo *splay_tree,