cpufreq: Use cpumask_copy instead of cpumask_or to copy a mask

->related_cpus is empty at this point of time and copying ->cpus to it
or orring ->related_cpus with ->cpus would result in the same value. But
cpumask_copy makes it rather clear.
Reviewed-by: NSaravana Kannan <skannan@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/cpufreq.c

@@ -1214,7 +1214,7 @@ static int cpufreq_online(unsigned int cpu)
 
 	if (new_policy) {
 		/* related_cpus should at least include policy->cpus. */
-		cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);
+		cpumask_copy(policy->related_cpus, policy->cpus);
 		/* Remember CPUs present at the policy creation time. */
 		cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask);
 	}