doc: ReSTify SELinux.txt

Adjusts for ReST markup and moves under LSM admin guide.

Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/scripts/selinux/README b/scripts/selinux/README
index 4d020ec..5ba679c5 100644
--- a/scripts/selinux/README
+++ b/scripts/selinux/README
@@ -1,2 +1,2 @@
-Please see Documentation/security/SELinux.txt for information on
+Please see Documentation/admin-guide/LSM/SELinux.rst for information on
 installing a dummy SELinux policy.