cpufreq: governor: Free dbs_data directly when gov->init() fails

Due to the kobject embedded in the dbs_data doest not has a release()
method yet, it needs to use kfree() to free dbs_data directly when
governor fails to allocate the tunner field of dbs_data.

Signed-off-by: Liao Chang <liaochang1@huawei.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>