patch 8.1.1304: MS-Windows: compiler warning for unused value

Problem:    MS-Windows: compiler warning for unused value.
Solution:   Adjust #ifdefs. (Ken Takata, closes #4363)
diff --git a/src/version.c b/src/version.c
index 8aef9dd..7715410 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1304,
+/**/
     1303,
 /**/
     1302,