patch 9.1.0888: leftcol property not available in getwininfo()

Problem:  leftcol property not available in getwininfo()
Solution: add leftcol property property (glepnir)

closes: #16119

Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt
index e763da0..d0f0c7b 100644
--- a/runtime/doc/builtin.txt
+++ b/runtime/doc/builtin.txt
@@ -1,4 +1,4 @@
-*builtin.txt*	For Vim version 9.1.  Last change: 2024 Nov 18
+*builtin.txt*	For Vim version 9.1.  Last change: 2024 Nov 26
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -5086,6 +5086,8 @@
 			botline		last complete displayed buffer line
 			bufnr		number of buffer in the window
 			height		window height (excluding winbar)
+			leftcol		first column displayed; only used when
+					'wrap' is off
 			loclist		1 if showing a location list
 					{only with the +quickfix feature}
 			quickfix	1 if quickfix or location list window