patch 8.1.0268: file type checking has too many #ifdef

Problem:    File type checking has too many #ifdef.
Solution:   Always define the S_IF macros. (Ken Takata, closes #3306)
diff --git a/src/version.c b/src/version.c
index 2e9ecf7..d71ee0e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    268,
+/**/
     267,
 /**/
     266,