patch 9.0.1317: crash when using an unset object variable

Problem:    Crash when using an unset object variable.
Solution:   Give an error instead. (closes #12005)
diff --git a/src/version.c b/src/version.c
index 6cd2f16..ff0b29e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1317,
+/**/
     1316,
 /**/
     1315,