vim-patch:7.4.597 #2658

Problem:    Cannot change the result of systemlist().
Solution:   Initialize v_lock. (Yukihiro Nakadaira)

https://github.com/vim/vim/commit/v7-4-597

See https://groups.google.com/d/msg/vim_dev/WXCfHMeqjfk/n2PjNwZ2bzIJ

src/nvim/version.c

@@ -203,7 +203,7 @@ static int included_patches[] = {
   //600,
   599,
   //598,
-  //597,
+  597,
   //596 NA
   595,
   594,