Another forward declaration to appease perl 5.6

tmcd/ron/vnodesetup

@@ -41,6 +41,11 @@ delete @ENV{'IFS', 'CDPATH', 'ENV', 'BASH_ENV'};
 use lib "/usr/local/etc/testbed";
 use libsetup;
 
+#
+# Forward declarations for prototype checking
+#
+sub killvnode();
+
 #
 # Parse command arguments. Once we return from getopts, all that should be
 # left are the required arguments.