patch 9.0.0406: deferred functions not invoked when partial func exits

Problem:    Deferred functions not invoked when partial func exits.
Solution:   Create a funccall_T when calling a :def function.
diff --git a/src/version.c b/src/version.c
index ff5fd12..e4b0b09 100644
--- a/src/version.c
+++ b/src/version.c
@@ -704,6 +704,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    406,
+/**/
     405,
 /**/
     404,