upstream: permitlisten option for authorized_keys; ok markus@

OpenBSD-Commit-ID: 8650883018d7aa893173d703379e4456a222c672
diff --git a/auth-options.h b/auth-options.h
index bf59b30..0462983 100644
--- a/auth-options.h
+++ b/auth-options.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth-options.h,v 1.26 2018/03/12 00:52:01 djm Exp $ */
+/* $OpenBSD: auth-options.h,v 1.27 2018/06/06 18:23:32 djm Exp $ */
 
 /*
  * Copyright (c) 2018 Damien Miller <djm@mindrot.org>
@@ -55,6 +55,10 @@
 	size_t npermitopen;
 	char **permitopen;
 
+	/* Permitted listens (remote forwarding) */
+	size_t npermitlisten;
+	char **permitlisten;
+
 	/*
 	 * Permitted host/addresses (comma-separated)
 	 * Caller must check source address matches both lists (if present).