src/drivers: Use SPDX for GPL-2.0-only files

Done with sed and God Lines. Only done for C-like code for now.

Change-Id: I38eaffa391ed5971217ffad74a312b1641e431c9
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40051
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/drivers/i2c/ck505/ck505.c b/src/drivers/i2c/ck505/ck505.c
index 4baa1bc..23fba47 100644
--- a/src/drivers/i2c/ck505/ck505.c
+++ b/src/drivers/i2c/ck505/ck505.c
@@ -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. */
 
 #include <assert.h>
 #include <console/console.h>