arm64: tegra: Combine AGX Orin board files

arm64: tegra: Combine AGX Orin board files

The current AGX Orin structure has both a top-level module+board
file as well as a board file. Most of the data in the board-file
is closely related to the module itself. The benefit of this
extra file is outweighed by the additional complexity. Merge
the board file into the module+board file for simplicity.

Signed-off-by: Dara Stotland <dstotland@nvidia.com>
Reviewed-by: Brad Griffis <bgriffis@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>