patch 9.0.2030: no max callback recursion limit

Problem:  no max callback recursion limit
Solution: bail out, if max call recursion for callback functions
          has been reached.

This checks the 'maxfuncdepth' setting and throws E169 when a callback
function recursively calls itself.

closes: #13337
closes: #13339

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 502e77b..492c7da 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 9.0.  Last change: 2023 Aug 15
+*options.txt*	For Vim version 9.0.  Last change: 2023 Oct 14
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -5485,6 +5485,7 @@
 	Increasing this limit above 200 also changes the maximum for Ex
 	command recursion, see |E169|.
 	See also |:function|.
+	Also used for maximum depth of callback functions.
 
 						*'maxmapdepth'* *'mmd'* *E223*
 'maxmapdepth' 'mmd'	number	(default 1000)