license change

llvm-svn: 119395
diff --git a/libcxx/include/csignal b/libcxx/include/csignal
index 959f8b8..93adc59 100644
--- a/libcxx/include/csignal
+++ b/libcxx/include/csignal
@@ -3,8 +3,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//