patch 8.1.2221: cannot filter :disp output

Problem:    Cannot filter :disp output.
Solution:   Support filtereing :disp output. (Andi Massimino, closes #5117)
diff --git a/src/version.c b/src/version.c
index e348c32..718ad65 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2221,
+/**/
     2220,
 /**/
     2219,