x86/cpu: Add model number for Intel Clearwater Forest processor

Server product based on the Atom Darkmont core.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240117191844.56180-1-tony.luck@intel.com