platform/x86: mlx-platform: Add more reset cause attributes

Add more attributes for reset cause indication for the cases when
system reset has been caused by watchdog, BIOS reload and COMEX
thermal shutdown.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>