IVGCVSW-1807 : change license text in file headers

All changes are the same:

   //
   // Copyright © 2017 ARM Ltd. All rights reserved.
  -// See LICENSE file in the project root for full license information.
  +// SPDX-License-Identifier: MIT
   //

Change-Id: I37eae011411133663ca9d2b059714d92f8bf8e24
diff --git a/Android.mk b/Android.mk
index eae4573..89a7124 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1,6 +1,6 @@
 #
 # Copyright © 2017 ARM Ltd. All rights reserved.
-# See LICENSE file in the project root for full license information.
+# SPDX-License-Identifier: MIT
 #
 
 LOCAL_PATH := $(call my-dir)