cpufreq: cpufreq-dt: fix potential double put of cpu OF node

If cpufreq_generic_init() fails we jump into the resource
cleanup path which contains a of_node_put() call. Another
instance of this has already been called at that time
resulting a double decrement of the refcount.

Fix this by calling of_node_put() only after we are sure
that nothing has gone wrong.

Fixes: d2f31f1d "cpufreq: cpu0: Move per-cluster initialization code to ->init()"
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>