patch 8.2.0500: using the same loop in many places

Problem:    Using the same loop in many places.
Solution:   Define more FOR_ALL macros. (Yegappan Lakshmanan, closes #5339)
diff --git a/src/if_ruby.c b/src/if_ruby.c
index 80481e7..9b6d388 100644
--- a/src/if_ruby.c
+++ b/src/if_ruby.c
@@ -1147,7 +1147,7 @@
 
 	if (list != NULL)
 	{
-	    for (curr = list->lv_first; curr != NULL; curr = curr->li_next)
+	    FOR_ALL_LIST_ITEMS(list, curr)
 		rb_ary_push(result, vim_to_ruby(&curr->li_tv));
 	}
     }