src/southbridge: Add and update license headers

This change adds and updates headers in all of the southbridge files
that had missing or unrecognized headers.  After this goes in, we can
turn on lint checking for headers in all southbridge directories.

Change-Id: I09614730bfd4db923dda103bd07bab02836a4c92
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/26570
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
diff --git a/src/southbridge/amd/cimx/sb800/gpio_oem.h b/src/southbridge/amd/cimx/sb800/gpio_oem.h
index e2c81fc..9063b2b 100644
--- a/src/southbridge/amd/cimx/sb800/gpio_oem.h
+++ b/src/southbridge/amd/cimx/sb800/gpio_oem.h
@@ -1,3 +1,16 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
 #ifndef _CIMX_SB_GPIO_OEM_H_
 #define _CIMX_SB_GPIO_OEM_H_