patch 8.0.1538: popupmenu is too far left when completion is long

Problem:    Popupmenu is too far left when completion is long. (Linwei)
Solution:   Adjust column computations. (Hirohito Higashi, closes #2661)
diff --git a/src/version.c b/src/version.c
index ede62c9..d434ea1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -779,6 +779,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1538,
+/**/
     1537,
 /**/
     1536,