patch 8.1.0438: the ex_make() function is too long

Problem:    The ex_make() function is too long.
Solution:   Split it into several functions. (Yegappan Lakshmanan)
diff --git a/src/version.c b/src/version.c
index 55d3d80..f4e0508 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    438,
+/**/
     437,
 /**/
     436,