uboot-imx

arm64: dt: poplar: add optee node

As Poplar supports running TF-A with OP-TEE as BL32
payload, add op-tee node in DT, which enables usage of
OP-TEE driver (which provides an interface for requesting services
from OP-TEE).

Signed-off-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>