Added configure check for readlink.

diff --git a/configure b/configure
index 7ad9bc2..aeff6d6 100755
--- a/configure
+++ b/configure
@@ -15484,6 +15484,7 @@
 
 
 
+
 for ac_func in \
 	_lwp_create \
 	_lwp_self \
@@ -15519,6 +15520,7 @@
 	popen \
 	pread \
 	pwrite \
+	readlink \
 	rfork \
 	select \
 	sendmsg \