correct to list ispunctrune properly

Reference: /n/atom/patch/applied/ispunctrman
Date: Thu Mar 13 15:25:25 CET 2014
Signed-off-by: quanstro@quanstro.net

--- /sys/man/2/isalpharune	Thu Mar 13 15:25:11 2014
+++ /sys/man/2/isalpharune	Thu Mar 13 15:25:11 2014
@@ -1,6 +1,6 @@
 .TH ISALPHARUNE 2
 .SH NAME
-isalpharune, isbaserune, islowerrune, isspacerune, istitlerune, isupperrune, isdigitrune, tobaserune, tolowerrune, totitlerune, toupperrune \- Unicode character classes and cases
+isalpharune, isbaserune, islowerrune, ispunctrune, isspacerune, istitlerune, isupperrune, isdigitrune, tobaserune, tolowerrune, totitlerune, toupperrune \- Unicode character classes and cases
 .SH SYNOPSIS
 .B #include <u.h>
 .br