tegra: config: nyan-big: Add options required by Chrome OS boot

We need to match the device tree in the FIT with the U-Boot model so we
can automatically select the right device tree. Also adjust the load address
so that the device tree is not in the way when a zImage kernel tries to
extract itself.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>