uboot-phytec

ARM: tegra: remove custom define for Jetson TK1

Now that Kconfig has a per-board option, we can use that directly rather
than inventing a custom define for the AS3722 code to determine which
board it's being built for.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>