patch 9.0.0661: multi-byte "lastline" in 'fillchars' does not work properly

Problem:    Multi-byte "lastline" item in 'fillchars' does not work properly
            when the window is two columns wide.
Solution:   Compute the text length correctly. (closes #11280)
diff --git a/src/version.c b/src/version.c
index 3adb513..e9cc0ec 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    661,
+/**/
     660,
 /**/
     659,