patch 8.1.2224: cannot build Amiga version

Problem:    Cannot build Amiga version.
Solution:   Add dummy mch_setmouse(). (Ola Söder, closes #5126)
diff --git a/src/version.c b/src/version.c
index b0fdab2..62a4888 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2224,
+/**/
     2223,
 /**/
     2222,