intel_pstate: Change the setpoint for Atom params

Change the setpoint for the Baytrail and Cherrytrail CPUs.  This
will cause more aggressive pstate selection and improves
performance on a variety of workloads with little power penalty.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>