arm64: tegra: Add ADMA node for Tegra210

Populate the ADMA node for Tegra210. The ADMA is used by the Audio
Processing Engine (APE) on Tegra210 for moving data between the APE
and system memory.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>