uboot-imx

arm64: versal: Add Xilinx Versal Virtual QEMU board

Virtual QEMU board is generating DTB self and putting it to
VERSAL_QEMU_DTB_ADDR address.
Board is using CONFIG_OF_BOARD which ensures that u-boot is aligned with
board created by QEMU.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>