s390: add a few more SPDX identifiers
Add the correct SPDX license to a few more files under arch/s390 and
drivers/s390 which have been missed to far.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kbuild b/arch/s390/Kbuild
index eae2c64..9fdff3f 100644
--- a/arch/s390/Kbuild
+++ b/arch/s390/Kbuild
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
obj-y += kernel/
obj-y += mm/
obj-$(CONFIG_KVM) += kvm/