cpufreq: remove setting of policy->cpu in policy->cpus during init

policy->cpu is copied into policy->cpus in cpufreq_online() before
calling into cpufreq_driver->init(). So there's no need to set the
same in the individual driver init() functions again.

This patch removes the redundant setting of policy->cpu in policy->cpus
in intel_pstate and cppc drivers.

Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>