patch 8.0.0371: leaking memory when setting v:completed_item

Problem:    Leaking memory when setting v:completed_item.
Solution:   Or the flags instead of setting them.
diff --git a/src/version.c b/src/version.c
index 1482343..d8940c7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    371,
+/**/
     370,
 /**/
     369,