arm64: tegra: Restructure Orin NX/Nano device tree

arm64: tegra: Restructure Orin NX/Nano device tree

The Orin NX and Orin Nano boards share a common carrier board and the
module boards for both platforms are very similar. Therefore,
restructure the Orin NX/Nano device-tree source files to adhere to a
simple hierarchical format. This will help make clear where changes
should go, and eliminates redundancy within the files.

Previously the carrier board file was independent. However, given
that it is so tightly coupled with the module design, it will be
more practical to combine files together for a simpler layout.

Following changes are made to restructure the device tree source files:
1) Change include hierarchy. Top-level dts includes board dtsi.
   Board dtsi includes module dtsi. Module dtsi includes SoC dtsi.
2) Data from the top level dts file that is common to both Orin NX
   and Orin Nano is in tegra234-p3768-0000+p3767.dtsi.
3) Only data that is unique to NX/Nano is present in the top-level dts.

Signed-off-by: Vedant Deshpande <vedantd@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>