cpufreq: ondemand: Don't keep a copy of freq_table pointer

There is absolutely no need to keep a copy to the freq-table in 'struct
od_policy_dbs_info'. Use policy->freq_table instead.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>