arm64: tegra: Enable UARTA and UARTE for Orin Nano

Activate UARTA and UARTE functionalities for Orin Nano.

- UARTA is accessible via the 40-pin header with pin 8 and 10 (TX/RX)
- UARTE utilizes the M2.E connector

Signed-off-by: Gautham Srinivasan <gauthams@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>