patch 9.0.0643: smoothscroll test fails

Problem:    Smoothscroll test fails.
Solution:   Check if skipcol changed.
diff --git a/src/version.c b/src/version.c
index 786a866..a228d74 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    643,
+/**/
     642,
 /**/
     641,