patch 8.1.1224: MS-Windows: cannot specify font weight

Problem:    MS-Windows: cannot specify font weight.
Solution:   Add the "W" option to 'guifont'. (closes #4309)  Move GUI font
            explanation out of options.txt.
diff --git a/src/version.c b/src/version.c
index fdbb9a6..ae93dc3 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1224,
+/**/
     1223,
 /**/
     1222,