powercap: RAPL: Add Power Limit4 support for RaptorLake

Add RaptorLake to the list of processor models for which Power Limit4
is supported by the Intel RAPL driver.

Signed-off-by: Sumeet Pawnikar <sumeet.r.pawnikar@intel.com>
[ rjw: Changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>