cpufreq: intel_pstate: Add support for Gemini Lake

Use same parameters as INTEL_FAM6_ATOM_GOLDMONT to enable
Gemini Lake.

Signed-off-by: Box, David E <david.e.box@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>