patch 9.0.1121: cursor positioning and display problems with 'smoothscroll'

Problem:    Cursor positioning and display problems with 'smoothscroll' and
            using "zt", "zb" or "zz".
Solution:   Adjust computations and conditions. (Yee Cheng Chin,
            closes #11764)
diff --git a/src/version.c b/src/version.c
index 230db82..ae993ff 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1121,
+/**/
     1120,
 /**/
     1119,