ttyname_r on OSF/1

On OSF/1, I'm seeing this test failure in an *interactive* "make check" of
a ptsname_r testdir:

  test-ptsname_r.c:193: assertion failed
  FAIL: test-ptsname_r

It turns out the cause is a bug in gnulib's ttyname_r: It fails to add a
trailing NUL byte to the output string. This fixes it.

2012-06-24  Bruno Haible  <bruno <at> clisp.org>

	ttyname_r: Fix result on OSF/1, Solaris.
	* lib/ttyname_r.c (ttyname_r): Produce a NUL-terminated result.

--- lib/ttyname_r.c.orig	Sun Jun 24 22:37:31 2012
+++ lib/ttyname_r.c	Sun Jun 24 22:33:15 2012
 <at>  <at>  -45,7 +45,7  <at>  <at> 
     return err;
   if (buflen < sizeof (largerbuf))
     {
-      size_t namelen = strlen (largerbuf);
+      size_t namelen = strlen (largerbuf) + 1;
       if (namelen > buflen)
         return ERANGE;
       memcpy (buf, largerbuf, namelen);