thermal: intel: hfi: Disable an HFI instance when all its CPUs go offline

In preparation to support hibernation, add functionality to disable an HFI
instance during CPU offline. The last CPU of an instance that goes offline
will disable such instance.

The Intel Software Development Manual states that the operating system must
wait for the hardware to set MSR_IA32_PACKAGE_THERM_STATUS[26] after
disabling an HFI instance to ensure that it will no longer write on the HFI
memory. Some processors, however, do not ever set such bit. Wait a minimum
of 2ms to give time hardware to complete any pending memory writes.

Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>