platform/x86: intel_scu_wdt: Get rid of custom x86 model comparison

Switch the platform code to use x86_id_table and accompanying API
instead of custom comparison against x86 CPU model.

This is one of the last users of custom API for that and following
changes will remove it for the good.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>