patch 8.2.1905: the wininfo list may contain stale entries

Problem:    The wininfo list may contain stale entries.
Solution:   When closing a window remove any other entry where the window
            pointer is NULL.
diff --git a/src/version.c b/src/version.c
index 2d36060..1cde8c7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1905,
+/**/
     1904,
 /**/
     1903,