patch 8.2.3252: duplicated code for adding buffer lines

Problem:    Duplicated code for adding buffer lines.
Solution:   Move code to a common function.  Also move map functions to map.c.
            (Yegappan Lakshmanan, closes #8665)

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3252,
 /**/
     3251,
 /**/