ARM: tegra: add APB DMA controller to Tegra124 DT

Instantiate the APB DMA controller in the Tegra124 DT, and add all
DMA-related properties to other DT nodes that rely on (reference) the
DMA controller's node.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>