patch 9.1.0818: some global functions are only used in single files

Problem:  some global functions are only used in single files
Solution: refactor code slightly and make some more functions static
          (Yegappan Lakshmanan)

closes: #15951

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index 90fc3b3..02e24d5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    818,
+/**/
     817,
 /**/
     816,