platform: mellanox: Introduce support of Nvidia smart switch

Provide platform support for Nvidia Smart Switch SN4280.

The Smart Switch equipped with:
- Nvidia COME module based on AMD EPYC™ Embedded 3451 CPU.
- Nvidia Spectrum-3 ASIC.
- Four DPUs, each equipped with Nvidia BF3 ARM based processor and
  with Lattice LFD2NX-40 FPGA device.
- 28xQSFP-DD external ports.
- Two power supplies.
- Four cooling drawers.

Reviewed-by: Ciju Rajan K <crajank@nvidia.com>
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20250421092051.7687-3-vadimp@nvidia.com


Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>