patch 8.0.0606: cannot set the context for a specified quickfix list

Problem:    Cannot set the context for a specified quickfix list.
Solution:   Use the list index instead of the current list. (Yegappan
            Lakshmanan)
diff --git a/src/version.c b/src/version.c
index 2c5aa06..0daa349 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    606,
+/**/
     605,
 /**/
     604,