patch 8.0.0490: vertical split makes 'winfixwidth' window smaller

Problem:    Splitting a 'winfixwidth' window vertically makes it one column
            smaller. (Dominique Pelle)
Solution:   Add one to the width for the separator.
diff --git a/src/version.c b/src/version.c
index dd6e366..e009e8e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    490,
+/**/
     489,
 /**/
     488,