Dual-license IBM code contributions

It was brought to our attention that U-Boot contains code derived from the
IBM OpenBIOS source code originally provided with some of the older PowerPC
4xx development boards.  As a result, the original license of this code has
been carried in the various files for a number of years in the U-Boot project.

IBM is dual-licensing the IBM code contributions already present in U-Boot
under either the terms of the GNU General Public License version 2, or the
original code license already present.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
diff --git a/include/miiphy.h b/include/miiphy.h
index 32f0a61..fa33ec7 100644
--- a/include/miiphy.h
+++ b/include/miiphy.h
@@ -1,4 +1,6 @@
 /*----------------------------------------------------------------------------+
+|   This source code is dual-licensed.  You may use it under the terms of the
+|   GNU General Public License version 2, or under the license below.
 |
 |	This source code has been made available to you by IBM on an AS-IS
 |	basis.	Anyone receiving this source is licensed under IBM