arm64: tegra: Add NVIDIA P2771 board support

The NVIDIA P2771 is composed of a P3310 processor module that connects
to the P2597 I/O board. It comes with a 1200x1920 MIPI DSI panel that is
connected via the P2597's display connector and has several connectors
such as HDMI, USB 3.0, PCIe and ethernet.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>