patch 8.2.2559: MS-Windows: guifont test fails on Windows XP

Problem:    MS-Windows: guifont test fails on Windows XP.
Solution:   Check windowsversion().
diff --git a/src/version.c b/src/version.c
index b623c42..67fc08c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2559,
+/**/
     2558,
 /**/
     2557,