patch 8.1.0068: nasty autocommands can still cause using freed memory

Problem:    Nasty autocommands can still cause using freed memory.
Solution:   Disallow using setloclist() and setqflist() recursively.
diff --git a/src/version.c b/src/version.c
index 0ecc60c..e55be52 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    68,
+/**/
     67,
 /**/
     66,