soc/amd: replace remaining license headers with SPDX ones

Change-Id: Ib45e93faebc2d24389f8739911419dfec437bd59
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40505
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/soc/amd/picasso/Kconfig b/src/soc/amd/picasso/Kconfig
index 4759f01..c7e65fa 100644
--- a/src/soc/amd/picasso/Kconfig
+++ b/src/soc/amd/picasso/Kconfig
@@ -1,16 +1,5 @@
-##
-## 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.
-##
+# SPDX-License-Identifier: GPL-2.0-only
+# This file is part of the coreboot project.
 
 config SOC_AMD_PICASSO
 	bool