patch 9.0.1642: build failure with tiny features

Problem:    Build failure with tiny features.
Solution:   Add #ifdef's.
diff --git a/src/version.c b/src/version.c
index 08762fd..1d29427 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1642,
+/**/
     1641,
 /**/
     1640,