arm64: dts: imx: Switch to using upstream DT on DH i.MX8MP DHCOM PDK2/PDK3

Enable OF_UPSTREAM to use upstream DT and add freescale/ prefix to the
DEFAULT_DEVICE_TREE. And thereby directly build DTB from dts/upstream/src/
including *-u-boot.dtsi and DTBOs from arch/$(ARCH)/dts/ directory.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Marek Vasut <marex@denx.de>
5 files changed