patch 8.2.3320: some local functions are not static

Problem:    Some local functions are not static.
Solution:   Add "static".  Move snprintf() related code to strings.c.
            (Yegappan Lakshmanan, closes #8734)

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3320,
 /**/
     3319,
 /**/