ARM: tegra: Add Avionic Design Tamonten support

The Tamonten is an NVIDIA Tegra2 based system-on-module (SOM) that is
designed to cover a broad range of applications.

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