Boot script support brings TEC in line with other Tegra boards. To
enable booting a Linux kernel with initial ramdisk, also include support
for the new FIT image type.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>