patch 8.1.0854: xxd does not work with more than 32 bit addresses

Problem:    xxd does not work with more than 32 bit addresses.
Solution:   Add support for 64 bit addresses. (Christer Jensen, closes #3791)
diff --git a/src/version.c b/src/version.c
index 97ef0c1..c119643 100644
--- a/src/version.c
+++ b/src/version.c
@@ -784,6 +784,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    854,
+/**/
     853,
 /**/
     852,