src/lib/: Remove "this file is part of" line

Change-Id: I9031dad52581e77aa56014b1fede884f2cdeb6de
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49882
Reviewed-by:  Felix Singer <felixsinger@posteo.net>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/lib/Kconfig.cbfs_verification

@@ -1,7 +1,5 @@
 # SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0-or-later
 #
-# This file is part of the coreboot project.
-#
 # This file is sourced from src/security/Kconfig for menuconfig convenience.
 
 #menu "CBFS verification"	# TODO: enable once it works