patch 8.2.3198: cannot use 'formatlistpat' for breakindent

Problem:    Cannot use 'formatlistpat' for breakindent.
Solution:   Use a negative list indent. (Maxim Kim, closes #8594)
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index aaac094..e5a76b7 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1326,9 +1326,11 @@
 			    continuation (positive).
 		sbr	    Display the 'showbreak' value before applying the
 			    additional indent.
-		list:{n}    Adds an additional indent for lines that match a 
+		list:{n}    Adds an additional indent for lines that match a
 			    numbered or bulleted list (using the
 			    'formatlistpat' setting).
+		list:-1	    Uses the length of a match with 'formatlistpat'
+			    for indentation.
 	The default value for min is 20, shift and list is 0.
 
 						*'browsedir'* *'bsdir'*