cpufreq: cpu0: drop wrong devm usage

This driver is using devres managed calls incorrectly, giving the cpu0
device as first parameter instead of the cpufreq platform device.
This results in resources not being freed if the cpufreq platform device
is unbound, for example if probing has to be deferred for a missing
regulator.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>