patch 8.1.0656: trying to reconnect to X server may cause problems

Problem:    Trying to reconnect to X server may cause problems.
Solution:   Do no try reconnecting when exiting. (James McCoy)
diff --git a/src/version.c b/src/version.c
index 42ae469..a49edb7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -800,6 +800,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    656,
+/**/
     655,
 /**/
     654,