cleanup after gl_FUNC_READLINK, for gl_FUNC_SYMLINK test

[Ralf Wildenhues]

Existence of leftover conftest.lnk2 file from readlink test breaks the
gl_FUNC_SYMLINK test (wrongly returning 2 instead of 0).  OK to commit?

Cheers,
Ralf

        * m4/readlink.m4 (gl_FUNC_READLINK): Remove conftest.lnk2,
        to avoid failure of symlink test later.

diff --git a/m4/readlink.m4 b/m4/readlink.m4
index 4cbb4ac..36cd41f 100644
--- a/m4/readlink.m4
+++ b/m4/readlink.m4
@@ -1,4 +1,4 @@
-# readlink.m4 serial 8
+# readlink.m4 serial 9
 dnl Copyright (C) 2003, 2007, 2009, 2010 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -35,7 +35,7 @@ AC_DEFUN([gl_FUNC_READLINK],
       return readlink ("conftest.lnk2/", buf, sizeof buf) != -1;]])],
          [gl_cv_func_readlink_works=yes], [gl_cv_func_readlink_works=no],
          [gl_cv_func_readlink_works="guessing no"])
-      rm -f conftest.link])
+      rm -f conftest.link conftest.lnk2])
     if test "$gl_cv_func_readlink_works" != yes; then
       AC_DEFINE([READLINK_TRAILING_SLASH_BUG], [1], [Define to 1 if readlink
         fails to recognize a trailing slash.])