Revert commit d0e936ad ("cpufreq: intel_pstate: Process HWP
Guaranteed change notification"), because it causes a NULL pointer
dereference to occur on Lenovo X1 gen9 laptops due to an HWP
guaranteed performance change interrupt arriving prematurely.

This feature will be revisited in the next cycle.
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>