patch 9.1.0327: No support for using $XDG_CONFIG_HOME

Problem:  No support for using $XDG_CONFIG_HOME
Solution: optionally source $XDG_CONFIG_HOME/vim/vimrc
          (Luca Saccarola)

fixes: #2034
closes: #14182

Signed-off-by: Luca Saccarola <github.e41mv@aleeas.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/version9.txt b/runtime/doc/version9.txt
index 69604e9..c277923 100644
--- a/runtime/doc/version9.txt
+++ b/runtime/doc/version9.txt
@@ -41543,6 +41543,8 @@
 
 Support for Wayland UI.
 
+Support for the XDG Desktop Specification |xdg-base-dir|
+
 Vim9 script
 -----------
 Add support for internal builtin functions with vim9 objects, see