uboot-phytec

ARM: DTS: Provide vf610-bk4r1-u-boot.dtsi for U-Boot specific properties

This commit brings a separate file in which the U-Boot specific
properties (like 'dm-pre-reloc') are provided.

Such approach allows easy sync with upstream Linux kernel in the
future.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>