patch 8.2.0017: OS/2 and MS-DOS are still mentioned

Problem:    OS/2 and MS-DOS are still mentioned, even though support was
            removed long ago.
Solution:   Update documentation. (Yegappan Lakshmanan, closes #5368)
diff --git a/runtime/doc/change.txt b/runtime/doc/change.txt
index a4b7fab..1acb267 100644
--- a/runtime/doc/change.txt
+++ b/runtime/doc/change.txt
@@ -611,7 +611,7 @@
 all files in it are deleted.  When Vim has the setuid bit set this may cause
 problems, the temp file is owned by the setuid user but the filter command
 probably runs as the original user.
-On MS-DOS and OS/2 the first of these directories that works is used: $TMP,
+On MS-Windows the first of these directories that works is used: $TMP,
 $TEMP, c:\TMP, c:\TEMP.
 For Unix the list of directories is: $TMPDIR, /tmp, current-dir, $HOME.
 For MS-Windows the GetTempFileName() system function is used.