platform: mellanox: mlx-platform: Add reset cause attribute

Extend IO registers description for some system types with reset cause
attribute "reset_swb_dc_dc_pwr_fail" to indicate reset caused by switch
board DC-DC power failure.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230822113451.13785-6-vadimp@nvidia.com


Signed-off-by: Hans de Goede <hdegoede@redhat.com>