Add device trees from Linux in preparation for driver model
conversions.

device tree files taken from Linux:
71ae5fc87c34: "Merge tag 'linux-kselftest-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest"

and added SPDX license identifier.
Signed-off-by: NHeiko Schocher <hs@denx.de>